Let's try this. It's BUGGERED.

29 files changed, 3679 insertions, 0 deletions

diff --git a/src/cmd/eqn/diacrit.c b/src/cmd/eqn/diacrit.c
new file mode 100644
index 00000000..10dc8c75
--- /dev/null
+++ b/src/cmd/eqn/diacrit.c
@@ -0,0 +1,75 @@
+#include "e.h"
+#include "y.tab.h"
+
+extern double Dvshift, Dhshift, Dh2shift, Dheight, Barv, Barh, Ubarv, Ubarh;
+
+void diacrit(int p1, int type)
+{
+	int c, t;
+
+	c = salloc();
+	t = salloc();
+	nrwid(p1, ps, p1);
+	printf(".nr 10 %gm\n", max(REL(eht[p1]-ebase[p1]-1,ps), 0));	/* vert shift if high */
+	if (type == HIGHBAR)
+		printf(".nr 10 \\n(10+%gm\n", Dvshift);
+	else if (type == LOWBAR)
+		printf(".nr 10 0\n");
+	else
+		printf(".if \\n(ct>1 .nr 10 \\n(10+%gm\n", Dvshift);
+	printf(".nr %d %gm\n", t, Dhshift);	/* horiz shift if high */
+	printf(".if \\n(ct>1 .nr %d %gm\n", t, Dh2shift);	/* was .1 and .15 */
+	switch (type) {
+	case VEC:
+		printf(".ds %d %s\n", c, lookup(deftbl, "vec_def")->cval);
+		break;
+	case DYAD:
+		printf(".ds %d %s\n", c, lookup(deftbl, "dyad_def")->cval);
+		break;
+	case HAT:
+		printf(".ds %d %s\n", c, lookup(deftbl, "hat_def")->cval);
+		break;
+	case TILDE:
+		printf(".ds %d %s\n", c, lookup(deftbl, "tilde_def")->cval);
+		break;
+	case DOT:
+		printf(".ds %d %s\n", c, lookup(deftbl, "dot_def")->cval);
+		break;
+	case DOTDOT:
+		printf(".ds %d %s\n", c, lookup(deftbl, "dotdot_def")->cval);
+		break;
+	case BAR:
+	case LOWBAR:
+	case HIGHBAR:
+		printf(".ds %d \\v'%gm'\\h'%gm'\\l'\\n(%du-%gm'\\h'%gm'\\v'%gm'\n",
+			c, -Barv, Barh, p1, 2*Barh, Barh, Barv);
+		break;
+	case UNDER:
+		printf(".ds %d \\v'%gm'\\l'\\n(%du-%gm\\(ul'\\h'%gm'\\v'%gm'\n",
+			c, -Ubarv, p1, Ubarh, Ubarh, Ubarv);
+		/* printf(".ds %d \\v'-%gm'\\l'\\n(%du\\(ul'\\v'%gm'\n",
+			c, Ubarv, p1, Ubarv);
+		*/
+		printf(".nr %d 0\n", t);
+		printf(".nr 10 0-.1m-%gm\n", REL(ebase[p1],ps));
+		printf(".if \\n(ct%%2=1 .nr 10 0\\n(10-.1m\n");
+		break;
+	case UTILDE:
+		printf(".ds %d %s\n", c, lookup(deftbl, "utilde_def")->cval);
+		printf(".nr %d 0\n", t);
+		printf(".nr 10 0-%gm\n", REL(ebase[p1],ps));
+		printf(".if \\n(ct%%2=1 .nr 10 0\\n(10-%gm\n", 0.1);
+		break;
+	}
+	nrwid(c, ps, c);
+	if (lfont[p1] != ITAL)
+		printf(".nr %d 0\n", t);
+	printf(".as %d \\h'-\\n(%du-\\n(%du/2u+\\n(%du'\\v'0-\\n(10u'\\*(%d", 
+		p1, p1, c, t, c);
+	printf("\\v'\\n(10u'\\h'-\\n(%du+\\n(%du/2u-\\n(%du'\n", c, p1, t);
+	if (type != UNDER && type != UTILDE)
+		eht[p1] += EM(Dheight, ps);	/* was .15 */
+	dprintf(".\tdiacrit: %c over S%d, lf=%c, rf=%c, h=%g, b=%g\n",
+		type, p1, lfont[p1], rfont[p1], eht[p1], ebase[p1]);
+	sfree(c); sfree(t);
+}
diff --git a/src/cmd/eqn/e.h b/src/cmd/eqn/e.h
new file mode 100644
index 00000000..70c47023
--- /dev/null
+++ b/src/cmd/eqn/e.h
@@ -0,0 +1,166 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+enum charclass {
+	OTHER, OLET, ILET, DIG, LPAR, RPAR, SLASH, PLUS, ILETF, ILETJ, VBAR,
+	NONE, LAST
+};
+extern int class[LAST][LAST];
+
+#define	dprintf		if (dbg) printf
+#define	max(x,y)	(((x) >= (y)) ? (x) : (y))	/* beware of side effects */
+#define	min(x,y)	(((x) <= (y)) ? (x) : (y))
+
+extern	char	errbuf[200];
+extern	char	*cmdname;
+#define	ERROR	sprintf(errbuf,
+#define	FATAL	), error(1, errbuf)
+#define	WARNING	), error(0, errbuf)
+#define	SYNTAX	), yyerror(errbuf)
+
+#define	ROM	'1'
+#define	ITAL	'2'
+#define	BLD	'3'
+#define	BDIT	'4'
+
+#define	DEFGAP	-999	/* default gap in piles */
+
+extern int	dbg;
+extern int	ct;
+extern int	lp[];
+extern int	used[];		/* available registers */
+extern int	ps;		/* dflt init pt size */
+extern int	deltaps;	/* default change in ps */
+extern int	dps_set;	/* 1 => -p option used */
+extern int	gsize;		/* global size */
+extern int	ft;		/* default font */
+extern int	display;	/* 1 => inline, 0 => .EQ/.EN */
+extern int	synerr;		/* 1 if syntax error in this eqn */
+
+extern char	*typesetter;	/* typesetter name for -T... */
+extern int	minsize;	/* min size it can print */
+extern int	ttype;		/* actual type of typesetter: */
+
+#define	DEVCAT	1
+#define	DEV202	2
+#define	DEVAPS	3
+#define	DEVPOST	4
+
+extern double	eht[];
+extern double	ebase[];
+extern int	lfont[];
+extern int	rfont[];
+extern int	lclass[];
+extern int	rclass[];
+extern int	yyval;
+extern int	yylval;
+extern int	eqnreg;
+extern double	eqnht;
+extern int	lefteq, righteq;
+extern int	markline;	/* 1 if this EQ/EN contains mark or lineup */
+
+#define	TBLSIZE	100
+
+typedef struct s_tbl {
+	char	*name;		/* e.g., "max" or "sum" */
+	char	*cval;		/* e.g., "\\f1max\\fP" */
+	int	ival;		/*    or SUM */
+	struct s_tbl *next;
+} tbl;
+
+extern	char	*spaceval;	/* use in place of normal \x (for pic) */
+
+#define	String	01
+#define	Macro	02
+#define	File	04
+#define	Char	010
+#define	Free	040
+
+typedef struct infile {
+	FILE	*fin;
+	char	*fname;
+	int	lineno;
+} Infile;
+
+typedef struct {	/* input source */
+	int	type;	/* Macro, String, File */
+	char	*sp;	/* if String or Macro */
+} Src;
+
+extern	Src	src[], *srcp;	/* input source stack */
+
+#define	MAXARGS	20
+typedef struct {	/* argument stack */
+	char	*argstk[MAXARGS];	/* pointers to args */
+	char	*argval;	/* points to space containing args */
+} Arg;
+
+typedef struct {	/* font number and name */
+	int	ft;
+	char	name[10];
+} Font;
+
+extern	Font	ftstack[];
+extern	Font	*ftp;
+
+extern	int	szstack[];
+extern	int	nszstack;
+
+extern	Infile	infile[10];
+extern	Infile	*curfile;
+
+extern	tbl	*lookup(tbl **tblp, char *name);
+extern	void	install(tbl **tblp, char *name, char *cval, int ival);
+extern	tbl	*keytbl[], *deftbl[], *restbl[], *ftunetbl[];
+
+extern	int	salloc(void);
+extern	void	sfree(int);
+extern	void	nrwid(int, int, int);
+extern	char	*ABSPS(int);
+extern	char	*DPS(int, int);
+extern	int	EFFPS(int);
+extern	double	EM(double, int);
+extern	double	REL(double, int);
+extern	char	*pad(int);
+extern	void	getstr(char *, int);
+extern	char	*strsave(char *);
+
+extern	int	input(void);
+extern	int	unput(int);
+extern	void	pbstr(char *);
+extern	void	error(int, char *);
+extern	void	yyerror(char *);
+
+extern	void	diacrit(int, int);
+extern	void	eqnbox(int, int, int);
+extern	void	setfont(char *);
+extern	void	font(int, int);
+extern	void	globfont(void);
+extern	void	fatbox(int);
+extern	void	fromto(int, int, int);
+extern	void	funny(int);
+extern	void	integral(int, int, int);
+extern	void	setintegral(void);
+extern	void	pushsrc(int, char *);
+extern	void	popsrc(void);
+extern	void	putout(int);
+extern	void	text(int, char *);
+extern void subsup(int, int, int);
+extern void bshiftb(int, int, int);
+extern void shift2(int, int, int);
+extern void setsize(char *);
+extern void size(int, int);
+extern void globsize(void);
+#define sqrt esqrt
+extern void sqrt(int);
+extern void text(int, char *);
+extern void boverb(int, int);
+extern void lineup(int);
+extern void mark(int);
+extern void paren(int, int, int);
+extern void move(int, int, int);
+extern void pile(int);
+extern int startcol(int);
+extern void column(int, int);
+extern void matrix(int);
diff --git a/src/cmd/eqn/eqn.c b/src/cmd/eqn/eqn.c
new file mode 100644
index 00000000..527e5e08
--- /dev/null
+++ b/src/cmd/eqn/eqn.c
@@ -0,0 +1,741 @@
+#define	CONTIG	57346
+#define	QTEXT	57347
+#define	SPACE	57348
+#define	THIN	57349
+#define	TAB	57350
+#define	MATRIX	57351
+#define	LCOL	57352
+#define	CCOL	57353
+#define	RCOL	57354
+#define	COL	57355
+#define	ABOVE	57356
+#define	MARK	57357
+#define	LINEUP	57358
+#define	SUM	57359
+#define	INT	57360
+#define	PROD	57361
+#define	UNION	57362
+#define	INTER	57363
+#define	DEFINE	57364
+#define	TDEFINE	57365
+#define	NDEFINE	57366
+#define	DELIM	57367
+#define	GSIZE	57368
+#define	GFONT	57369
+#define	INCLUDE	57370
+#define	IFDEF	57371
+#define	DOTEQ	57372
+#define	DOTEN	57373
+#define	FROM	57374
+#define	TO	57375
+#define	OVER	57376
+#define	SQRT	57377
+#define	SUP	57378
+#define	SUB	57379
+#define	SIZE	57380
+#define	FONT	57381
+#define	ROMAN	57382
+#define	ITALIC	57383
+#define	BOLD	57384
+#define	FAT	57385
+#define	UP	57386
+#define	DOWN	57387
+#define	BACK	57388
+#define	FWD	57389
+#define	LEFT	57390
+#define	RIGHT	57391
+#define	DOT	57392
+#define	DOTDOT	57393
+#define	HAT	57394
+#define	TILDE	57395
+#define	BAR	57396
+#define	LOWBAR	57397
+#define	HIGHBAR	57398
+#define	UNDER	57399
+#define	VEC	57400
+#define	DYAD	57401
+#define	UTILDE	57402
+
+#line	17	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+#include "e.h"
+
+int	yylex(void);
+extern	int	yyerrflag;
+#ifndef	YYMAXDEPTH
+#define	YYMAXDEPTH	150
+#endif
+#ifndef	YYSTYPE
+#define	YYSTYPE	int
+#endif
+YYSTYPE	yylval;
+YYSTYPE	yyval;
+#define YYEOFCODE 1
+#define YYERRCODE 2
+
+#line	140	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+
+short	yyexca[] =
+{-1, 0,
+	1, 3,
+	-2, 0,
+-1, 1,
+	1, -1,
+	-2, 0,
+};
+#define	YYNPROD	90
+#define	YYPRIVATE 57344
+#define	YYLAST	469
+short	yyact[] =
+{
+   4, 103, 119,  45,  27, 118, 104,   2, 102,  41,
+  42,  43,  44,  65,  80,  81,  79,  66,  67,  68,
+  69,  70,  50,  49,  74,  75,  76,  77, 105,  73,
+  40,  80,  81,  80,  81, 114,  61,  64,  54,  62,
+  57,  58,  59,  60,  55,  56,  63,  78,  91,  92,
+  82,  26,  83,  85,  86,  87,  88,  90,  51,  52,
+  48, 124,  50,  49, 117,  25,  45, 117,  72,  71,
+  80,  81, 113,  24,  45,  23,  61,  64,  54,  62,
+  57,  58,  59,  60,  55,  56,  63,  53,  89, 100,
+  84,  22,  96,  95, 106, 107, 108, 109,  99, 110,
+ 111,  41,  42,  43,  44,  45,  98, 115,  21,  94,
+  93,  18, 130, 123,  17, 116, 121,  46, 112, 125,
+ 127, 128,   1, 129, 126,   0,   0,  45,   8,   7,
+   9,  10,  11,  28,  41,  42,  43,  44,   0,  16,
+  47,  12,  34,  13,  14,  15,  61,  64,  54,  62,
+  57,  58,  59,  60,  55,  56,  63,   0,   0,  20,
+   0,   0,  29,  33,  30,  31,  32,  19,  37,  39,
+  38,  36,  35,   0,   0,   0,   0,   0,   0,   0,
+   0,   0,   0,   0,   0,   6,  97,   8,   7,   9,
+  10,  11,  28,  41,  42,  43,  44,   0,  16,  47,
+  12,  34,  13,  14,  15,   0,   0,   0,   0,   0,
+   0,   0,   0,   0,   0,   0,   0,   0,  20,   0,
+   0,  29,  33,  30,  31,  32,  19,  37,  39,  38,
+  36,  35, 101,   0,   0,   0,   0,   0,   0,   0,
+   0,   0,   0,   3,   6,   8,   7,   9,  10,  11,
+  28,  41,  42,  43,  44,   0,  16,   5,  12,  34,
+  13,  14,  15,   0,   0,   0,   0,   0,   0,   0,
+   0,   0,   0,   0,   0,   0,  20,   0,   0,  29,
+  33,  30,  31,  32,  19,  37,  39,  38,  36,  35,
+   0,   0,   8,   7,   9,  10,  11,  28,  41,  42,
+  43,  44,   6,  16,  47,  12,  34,  13,  14,  15,
+   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
+   0,   0,   0,  20,   0,   0,  29,  33,  30,  31,
+  32,  19,  37,  39,  38,  36,  35,   0,   0,   8,
+   7,   9,  10,  11,  28,  41,  42,  43,  44,   6,
+  16,   5,  12,  34,  13,  14,  15,   0,   0,   0,
+   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
+  20,   0,   0,  29,  33,  30,  31,  32,  19,  37,
+  39,  38,  36,  35,   8,   7,   9,  10,  11,  28,
+  41,  42,  43,  44,   0,  16,   6,  12,  34,  13,
+  14,  15,   0,   0,   0,   0,   0,   0,   0,   0,
+   0,   0,   0,   0,   0,  20,   0,   0,  29,  33,
+  30,  31,  32,  19,  37,  39,  38,  36,  35,  51,
+ 122,  48,   0,  50,  49,   0,   0,   0,   0,   0,
+   0,   6,   0,   0, 120,  49,   0,  61,  64,  54,
+  62,  57,  58,  59,  60,  55,  56,  63,  61,  64,
+  54,  62,  57,  58,  59,  60,  55,  56,  63
+};
+short	yypact[] =
+{
+ 241,-1000, 288,-1000,  26,-1000, 335,-1000,-1000,-1000,
+-1000,-1000,-1000,-1000,-1000,-1000, 380, 380, 380, 380,
+ 380,  32, 335, 380, 380, 380, 380,-1000,-1000,  66,
+-1000,-1000,-1000,  66,-1000,  29,  66,  66,  66,  66,
+  27,-1000,-1000,-1000,-1000,  26,-1000, 380, 380,-1000,
+-1000,-1000,-1000,-1000,-1000,-1000,-1000,-1000,-1000,-1000,
+-1000,-1000,-1000,-1000,-1000, 124,  26,  96,  96,  96,
+ -14,-1000,-1000, 183,  96,  96,  96,  96, -53,-1000,
+-1000,-1000,-1000,-1000,-1000,-1000,-1000,-1000,-1000, 335,
+-1000,  26, -14, 380, 380, 380, 380,-1000, 380, 380,
+-1000,  10,  91,  53, 288, -56, 408, -14, 397,  26,
+ 408, -14,-1000,-1000,  -1,-1000,-1000, 335, 335,-1000,
+ 380,-1000, 380,-1000,-1000,-1000, 288,  50, -14,  26,
+-1000
+};
+short	yypgo[] =
+{
+   0, 122,   6,   0, 117,   2, 116, 114, 111, 110,
+ 109, 108, 106,  98,  93,  92,  91,  89,  87,  75,
+  73,  65,  51,   4,  47,  35,  16,  30,   1,  28
+};
+short	yyr1[] =
+{
+   0,   1,   1,   1,   2,   2,   2,   2,   4,   5,
+   5,   6,   6,   3,   3,   3,   3,   3,   3,   3,
+   3,   3,   3,   3,   3,   3,   3,   3,   3,   9,
+   3,  10,   3,  12,   3,  13,   3,   3,  14,   3,
+  15,   3,   3,   3,   3,   3,   3,   3,   3,   3,
+  24,   3,  11,  19,  20,  21,  22,  18,  18,  18,
+  18,  18,  18,  18,  18,  18,  18,  18,  16,  16,
+  17,  17,  25,  25,  23,  29,  23,  27,  27,  27,
+  27,  28,  28,   7,   8,   8,   8,   8,  26,  26
+};
+short	yyr2[] =
+{
+   0,   1,   1,   0,   1,   2,   2,   1,   2,   2,
+   0,   2,   0,   3,   1,   1,   1,   1,   1,   1,
+   1,   1,   1,   3,   2,   2,   2,   2,   2,   0,
+   5,   0,   4,   0,   5,   0,   4,   1,   0,   5,
+   0,   4,   3,   2,   2,   2,   2,   2,   2,   1,
+   0,   5,   1,   2,   2,   2,   2,   1,   1,   1,
+   1,   1,   1,   1,   1,   1,   1,   1,   2,   2,
+   2,   2,   1,   2,   4,   0,   6,   1,   1,   1,
+   1,   1,   3,   2,   1,   1,   1,   2,   1,   1
+};
+short	yychk[] =
+{
+-1000,  -1,  -2,   2,  -3,  16,  61,   5,   4,   6,
+   7,   8,  17,  19,  20,  21,  15,  -7,  -8,  43,
+  35, -11, -16, -19, -20, -21, -22, -23,   9,  38,
+  40,  41,  42,  39,  18,  48,  47,  44,  46,  45,
+ -27,  10,  11,  12,  13,  -3,  -4,  16,  34,  37,
+  36,  32,  33, -18,  52,  58,  59,  54,  55,  56,
+  57,  50,  53,  60,  51,  -2,  -3,  -3,  -3,  -3,
+  -3,  37,  36,  -2,  -3,  -3,  -3,  -3, -24, -26,
+   4,   5, -26, -26,  61, -26, -26, -26, -26,  61,
+ -26,  -3,  -3,  -9, -10, -14, -15,  62, -12, -13,
+ -17,  49,  61, -28,  -2, -29,  -3,  -3,  -3,  -3,
+  -3,  -3, -26,  62, -25, -23,  62,  14,  61,  -5,
+  36,  -6,  33,  -5,  62, -23,  -2, -28,  -3,  -3,
+  62
+};
+short	yydef[] =
+{
+  -2,  -2,   1,   2,   4,   7,   0,  14,  15,  16,
+  17,  18,  19,  20,  21,  22,   0,   0,   0,   0,
+   0,  37,   0,   0,   0,   0,   0,  49,  50,   0,
+  84,  85,  86,   0,  52,   0,   0,   0,   0,   0,
+   0,  77,  78,  79,  80,   5,   6,   0,   0,  29,
+  31,  38,  40,  44,  57,  58,  59,  60,  61,  62,
+  63,  64,  65,  66,  67,   0,  24,  25,  26,  27,
+  28,  33,  35,  43,  45,  46,  47,  48,   0,  83,
+  88,  89,  87,  68,  69,  53,  54,  55,  56,   0,
+  75,   8,  23,   0,   0,   0,   0,  13,   0,   0,
+  42,   0,   0,   0,  81,   0,  10,  32,  12,  41,
+  10,  36,  70,  71,   0,  72,  74,   0,   0,  30,
+   0,  39,   0,  34,  51,  73,  82,   0,   9,  11,
+  76
+};
+short	yytok1[] =
+{
+   1,   0,   0,   0,   0,   0,   0,   0,   0,   0,
+   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
+   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
+   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
+   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
+   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
+   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
+   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
+   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
+   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
+   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
+   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
+   0,   0,   0,  61,   0,  62
+};
+short	yytok2[] =
+{
+   2,   3,   4,   5,   6,   7,   8,   9,  10,  11,
+  12,  13,  14,  15,  16,  17,  18,  19,  20,  21,
+  22,  23,  24,  25,  26,  27,  28,  29,  30,  31,
+  32,  33,  34,  35,  36,  37,  38,  39,  40,  41,
+  42,  43,  44,  45,  46,  47,  48,  49,  50,  51,
+  52,  53,  54,  55,  56,  57,  58,  59,  60
+};
+long	yytok3[] =
+{
+   0
+};
+#define YYFLAG 		-1000
+#define YYERROR		goto yyerrlab
+#define YYACCEPT	return(0)
+#define YYABORT		return(1)
+#define	yyclearin	yychar = -1
+#define	yyerrok		yyerrflag = 0
+
+#ifdef	yydebug
+#include	"y.debug"
+#else
+#define	yydebug		0
+char*	yytoknames[1];		/* for debugging */
+char*	yystates[1];		/* for debugging */
+#endif
+
+/*	parser for yacc output	*/
+
+int	yynerrs = 0;		/* number of errors */
+int	yyerrflag = 0;		/* error recovery flag */
+
+char*
+yytokname(int yyc)
+{
+	static char x[10];
+
+	if(yyc > 0 && yyc <= sizeof(yytoknames)/sizeof(yytoknames[0]))
+	if(yytoknames[yyc-1])
+		return yytoknames[yyc-1];
+	sprintf(x, "<%d>", yyc);
+	return x;
+}
+
+char*
+yystatname(int yys)
+{
+	static char x[10];
+
+	if(yys >= 0 && yys < sizeof(yystates)/sizeof(yystates[0]))
+	if(yystates[yys])
+		return yystates[yys];
+	sprintf(x, "<%d>\n", yys);
+	return x;
+}
+
+long
+yylex1(void)
+{
+	long yychar;
+	long *t3p;
+	int c;
+
+	yychar = yylex();
+	if(yychar <= 0) {
+		c = yytok1[0];
+		goto out;
+	}
+	if(yychar < sizeof(yytok1)/sizeof(yytok1[0])) {
+		c = yytok1[yychar];
+		goto out;
+	}
+	if(yychar >= YYPRIVATE)
+		if(yychar < YYPRIVATE+sizeof(yytok2)/sizeof(yytok2[0])) {
+			c = yytok2[yychar-YYPRIVATE];
+			goto out;
+		}
+	for(t3p=yytok3;; t3p+=2) {
+		c = t3p[0];
+		if(c == yychar) {
+			c = t3p[1];
+			goto out;
+		}
+		if(c == 0)
+			break;
+	}
+	c = 0;
+
+out:
+	if(c == 0)
+		c = yytok2[1];	/* unknown char */
+	if(yydebug >= 3)
+		printf("lex %.4lX %s\n", yychar, yytokname(c));
+	return c;
+}
+
+int
+yyparse(void)
+{
+	struct
+	{
+		YYSTYPE	yyv;
+		int	yys;
+	} yys[YYMAXDEPTH], *yyp, *yypt;
+	short *yyxi;
+	int yyj, yym, yystate, yyn, yyg;
+	YYSTYPE save1, save2;
+	int save3, save4;
+	long yychar;
+
+	save1 = yylval;
+	save2 = yyval;
+	save3 = yynerrs;
+	save4 = yyerrflag;
+
+	yystate = 0;
+	yychar = -1;
+	yynerrs = 0;
+	yyerrflag = 0;
+	yyp = &yys[-1];
+	goto yystack;
+
+ret0:
+	yyn = 0;
+	goto ret;
+
+ret1:
+	yyn = 1;
+	goto ret;
+
+ret:
+	yylval = save1;
+	yyval = save2;
+	yynerrs = save3;
+	yyerrflag = save4;
+	return yyn;
+
+yystack:
+	/* put a state and value onto the stack */
+	if(yydebug >= 4)
+		printf("char %s in %s", yytokname(yychar), yystatname(yystate));
+
+	yyp++;
+	if(yyp >= &yys[YYMAXDEPTH]) {
+		yyerror("yacc stack overflow");
+		goto ret1;
+	}
+	yyp->yys = yystate;
+	yyp->yyv = yyval;
+
+yynewstate:
+	yyn = yypact[yystate];
+	if(yyn <= YYFLAG)
+		goto yydefault; /* simple state */
+	if(yychar < 0)
+		yychar = yylex1();
+	yyn += yychar;
+	if(yyn < 0 || yyn >= YYLAST)
+		goto yydefault;
+	yyn = yyact[yyn];
+	if(yychk[yyn] == yychar) { /* valid shift */
+		yychar = -1;
+		yyval = yylval;
+		yystate = yyn;
+		if(yyerrflag > 0)
+			yyerrflag--;
+		goto yystack;
+	}
+
+yydefault:
+	/* default state action */
+	yyn = yydef[yystate];
+	if(yyn == -2) {
+		if(yychar < 0)
+			yychar = yylex1();
+
+		/* look through exception table */
+		for(yyxi=yyexca;; yyxi+=2)
+			if(yyxi[0] == -1 && yyxi[1] == yystate)
+				break;
+		for(yyxi += 2;; yyxi += 2) {
+			yyn = yyxi[0];
+			if(yyn < 0 || yyn == yychar)
+				break;
+		}
+		yyn = yyxi[1];
+		if(yyn < 0)
+			goto ret0;
+	}
+	if(yyn == 0) {
+		/* error ... attempt to resume parsing */
+		switch(yyerrflag) {
+		case 0:   /* brand new error */
+			yyerror("syntax error");
+			if(yydebug >= 1) {
+				printf("%s", yystatname(yystate));
+				printf("saw %s\n", yytokname(yychar));
+			}
+yyerrlab:
+			yynerrs++;
+
+		case 1:
+		case 2: /* incompletely recovered error ... try again */
+			yyerrflag = 3;
+
+			/* find a state where "error" is a legal shift action */
+			while(yyp >= yys) {
+				yyn = yypact[yyp->yys] + YYERRCODE;
+				if(yyn >= 0 && yyn < YYLAST) {
+					yystate = yyact[yyn];  /* simulate a shift of "error" */
+					if(yychk[yystate] == YYERRCODE)
+						goto yystack;
+				}
+
+				/* the current yyp has no shift onn "error", pop stack */
+				if(yydebug >= 2)
+					printf("error recovery pops state %d, uncovers %d\n",
+						yyp->yys, (yyp-1)->yys );
+				yyp--;
+			}
+			/* there is no state on the stack with an error shift ... abort */
+			goto ret1;
+
+		case 3:  /* no shift yet; clobber input char */
+			if(yydebug >= YYEOFCODE)
+				printf("error recovery discards %s\n", yytokname(yychar));
+			if(yychar == YYEOFCODE)
+				goto ret1;
+			yychar = -1;
+			goto yynewstate;   /* try again in the same state */
+		}
+	}
+
+	/* reduction by production yyn */
+	if(yydebug >= 2)
+		printf("reduce %d in:\n\t%s", yyn, yystatname(yystate));
+
+	yypt = yyp;
+	yyp -= yyr2[yyn];
+	yyval = (yyp+1)->yyv;
+	yym = yyn;
+
+	/* consult goto table to find next state */
+	yyn = yyr1[yyn];
+	yyg = yypgo[yyn];
+	yyj = yyg + yyp->yys + 1;
+
+	if(yyj >= YYLAST || yychk[yystate=yyact[yyj]] != -yyn)
+		yystate = yyact[yyg];
+	switch(yym) {
+		
+case 1:
+#line	24	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ putout(yypt[-0].yyv); } break;
+case 2:
+#line	25	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ ERROR "syntax error" WARNING; } break;
+case 3:
+#line	26	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ eqnreg = 0; } break;
+case 5:
+#line	30	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ eqnbox(yypt[-1].yyv, yypt[-0].yyv, 0); } break;
+case 6:
+#line	31	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ eqnbox(yypt[-1].yyv, yypt[-0].yyv, 1); } break;
+case 7:
+#line	32	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ lineup(0); } break;
+case 8:
+#line	35	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = yypt[-0].yyv; lineup(1); } break;
+case 9:
+#line	38	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = yypt[-0].yyv; } break;
+case 10:
+#line	39	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = 0; } break;
+case 11:
+#line	42	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = yypt[-0].yyv; } break;
+case 12:
+#line	43	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = 0; } break;
+case 13:
+#line	46	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = yypt[-1].yyv; } break;
+case 14:
+#line	47	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ text(QTEXT, (char *) yypt[-0].yyv); } break;
+case 15:
+#line	48	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ text(CONTIG, (char *) yypt[-0].yyv); } break;
+case 16:
+#line	49	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ text(SPACE, (char *) 0); } break;
+case 17:
+#line	50	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ text(THIN, (char *) 0); } break;
+case 18:
+#line	51	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ text(TAB, (char *) 0); } break;
+case 19:
+#line	52	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ funny(SUM); } break;
+case 20:
+#line	53	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ funny(PROD); } break;
+case 21:
+#line	54	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ funny(UNION); } break;
+case 22:
+#line	55	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ funny(INTER); } break;
+case 23:
+#line	56	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ boverb(yypt[-2].yyv, yypt[-0].yyv); } break;
+case 24:
+#line	57	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ mark(yypt[-0].yyv); } break;
+case 25:
+#line	58	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ size(yypt[-1].yyv, yypt[-0].yyv); } break;
+case 26:
+#line	59	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ font(yypt[-1].yyv, yypt[-0].yyv); } break;
+case 27:
+#line	60	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ fatbox(yypt[-0].yyv); } break;
+case 28:
+#line	61	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ sqrt(yypt[-0].yyv); } break;
+case 29:
+#line	62	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ps -= deltaps;} break;
+case 30:
+#line	62	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ subsup(yypt[-4].yyv, yypt[-1].yyv, yypt[-0].yyv); } break;
+case 31:
+#line	63	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ps -= deltaps;} break;
+case 32:
+#line	63	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ subsup(yypt[-3].yyv, 0, yypt[-0].yyv); } break;
+case 33:
+#line	64	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ps -= deltaps;} break;
+case 34:
+#line	64	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ integral(yypt[-4].yyv, yypt[-1].yyv, yypt[-0].yyv); } break;
+case 35:
+#line	65	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ps -= deltaps;} break;
+case 36:
+#line	65	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ integral(yypt[-3].yyv, 0, yypt[-0].yyv); } break;
+case 37:
+#line	66	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ integral(yypt[-0].yyv, 0, 0); } break;
+case 38:
+#line	67	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ps -= deltaps;} break;
+case 39:
+#line	67	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ fromto(yypt[-4].yyv, yypt[-1].yyv, yypt[-0].yyv); } break;
+case 40:
+#line	68	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ps -= deltaps;} break;
+case 41:
+#line	68	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ fromto(yypt[-3].yyv, 0, yypt[-0].yyv); } break;
+case 42:
+#line	69	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ paren(yypt[-2].yyv, yypt[-1].yyv, yypt[-0].yyv); } break;
+case 43:
+#line	70	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ paren(yypt[-1].yyv, yypt[-0].yyv, 0); } break;
+case 44:
+#line	71	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ diacrit(yypt[-1].yyv, yypt[-0].yyv); } break;
+case 45:
+#line	72	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ move(FWD, yypt[-1].yyv, yypt[-0].yyv); } break;
+case 46:
+#line	73	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ move(UP, yypt[-1].yyv, yypt[-0].yyv); } break;
+case 47:
+#line	74	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ move(BACK, yypt[-1].yyv, yypt[-0].yyv); } break;
+case 48:
+#line	75	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ move(DOWN, yypt[-1].yyv, yypt[-0].yyv); } break;
+case 49:
+#line	76	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ pile(yypt[-0].yyv); ct = yypt[-0].yyv; } break;
+case 50:
+#line	77	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{yyval=ct;} break;
+case 51:
+#line	77	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ matrix(yypt[-3].yyv); ct = yypt[-3].yyv; } break;
+case 52:
+#line	80	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ setintegral(); } break;
+case 53:
+#line	83	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = atoi((char *) yypt[-1].yyv); } break;
+case 54:
+#line	84	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = atoi((char *) yypt[-1].yyv); } break;
+case 55:
+#line	85	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = atoi((char *) yypt[-1].yyv); } break;
+case 56:
+#line	86	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = atoi((char *) yypt[-1].yyv); } break;
+case 57:
+#line	88	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = HAT; } break;
+case 58:
+#line	89	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = VEC; } break;
+case 59:
+#line	90	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = DYAD; } break;
+case 60:
+#line	91	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = BAR; } break;
+case 61:
+#line	92	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = LOWBAR; } break;
+case 62:
+#line	93	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = HIGHBAR; } break;
+case 63:
+#line	94	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = UNDER; } break;
+case 64:
+#line	95	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = DOT; } break;
+case 65:
+#line	96	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = TILDE; } break;
+case 66:
+#line	97	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = UTILDE; } break;
+case 67:
+#line	98	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = DOTDOT; } break;
+case 68:
+#line	101	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = ((char *)yypt[-0].yyv)[0]; } break;
+case 69:
+#line	102	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = '{'; } break;
+case 70:
+#line	105	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = ((char *)yypt[-0].yyv)[0]; } break;
+case 71:
+#line	106	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = '}'; } break;
+case 74:
+#line	113	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ column(yypt[-3].yyv, DEFGAP); } break;
+case 75:
+#line	114	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{yyval=atoi((char*)yypt[-0].yyv);} break;
+case 76:
+#line	114	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ column(yypt[-5].yyv, yypt[-3].yyv); } break;
+case 77:
+#line	117	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = startcol(LCOL); } break;
+case 78:
+#line	118	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = startcol(CCOL); } break;
+case 79:
+#line	119	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = startcol(RCOL); } break;
+case 80:
+#line	120	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = startcol(COL); } break;
+case 81:
+#line	123	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ lp[ct++] = yypt[-0].yyv; } break;
+case 82:
+#line	124	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ lp[ct++] = yypt[-0].yyv; } break;
+case 83:
+#line	127	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ yyval = ps; setsize((char *) yypt[-0].yyv); } break;
+case 84:
+#line	130	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ static char R[]="R"; setfont(R); } break;
+case 85:
+#line	131	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ static char I[]="I"; setfont(I); } break;
+case 86:
+#line	132	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ static char B[]="B"; setfont(B); } break;
+case 87:
+#line	133	"/usr/local/plan9/src/cmd/eqn/eqn.y"
+{ setfont((char *)yypt[-0].yyv); } break;
+	}
+	goto yystack;  /* stack new state and value */
+}
diff --git a/src/cmd/eqn/eqn.y b/src/cmd/eqn/eqn.y
new file mode 100644
index 00000000..74796d7f
--- /dev/null
+++ b/src/cmd/eqn/eqn.y
@@ -0,0 +1,140 @@
+%term	CONTIG QTEXT SPACE THIN TAB
+%term	MATRIX LCOL CCOL RCOL COL ABOVE
+%term	MARK LINEUP
+%term	SUM INT PROD UNION INTER
+%term	DEFINE TDEFINE NDEFINE DELIM GSIZE GFONT INCLUDE SPACE IFDEF
+%term	DOTEQ DOTEN
+
+%right	FROM TO
+%left	OVER SQRT
+%right	SUP SUB
+%right	SIZE FONT ROMAN ITALIC BOLD FAT
+%right	UP DOWN BACK FWD
+%left	LEFT RIGHT
+%right	DOT DOTDOT HAT TILDE BAR LOWBAR HIGHBAR UNDER VEC DYAD UTILDE
+
+%{
+#include "e.h"
+
+int	yylex(void);
+%}
+
+%%
+
+stuff	: eqn 		{ putout($1); }
+	| error		{ ERROR "syntax error" WARNING; }	/* should be SYNTAX */
+	|		{ eqnreg = 0; }
+	;
+
+eqn	: box
+	| eqn box	{ eqnbox($1, $2, 0); }
+	| eqn lineupbox	{ eqnbox($1, $2, 1); }
+	| LINEUP	{ lineup(0); }
+	;
+
+lineupbox: LINEUP box	{ $$ = $2; lineup(1); }
+	;
+
+sbox	: SUP box	%prec SUP	{ $$ = $2; }
+	|		%prec SUP	{ $$ = 0; }
+	;
+
+tbox	: TO box	%prec TO	{ $$ = $2; }
+	|		%prec FROM	{ $$ = 0; }
+	;
+
+box	: '{' eqn '}'	{ $$ = $2; }
+	| QTEXT		{ text(QTEXT, (char *) $1); }
+	| CONTIG	{ text(CONTIG, (char *) $1); }
+	| SPACE		{ text(SPACE, (char *) 0); }
+	| THIN		{ text(THIN, (char *) 0); }
+	| TAB		{ text(TAB, (char *) 0); }
+	| SUM		{ funny(SUM); }
+	| PROD		{ funny(PROD); }
+	| UNION		{ funny(UNION); }
+	| INTER		{ funny(INTER); }
+ 	| box OVER box			{ boverb($1, $3); }
+	| MARK box			{ mark($2); }
+	| size box	%prec SIZE	{ size($1, $2); }
+	| font box	%prec FONT	{ font($1, $2); }
+	| FAT box			{ fatbox($2); }
+	| SQRT box			{ sqrt($2); }
+	| box SUB {ps -= deltaps;} box sbox	%prec SUB	{ subsup($1, $4, $5); }
+	| box SUP {ps -= deltaps;} box		%prec SUP	{ subsup($1, 0, $4); }
+	| int SUB {ps -= deltaps;} box sbox	%prec SUB	{ integral($1, $4, $5); }
+	| int SUP {ps -= deltaps;} box		%prec SUP	{ integral($1, 0, $4); }
+	| int					{ integral($1, 0, 0); }
+	| box FROM {ps -= deltaps;} box tbox	%prec FROM	{ fromto($1, $4, $5); }
+	| box TO {ps -= deltaps;} box		%prec TO	{ fromto($1, 0, $4); }
+	| left eqn right			{ paren($1, $2, $3); }
+	| left eqn 				{ paren($1, $2, 0); }
+	| box diacrit			{ diacrit($1, $2); }
+	| fwd box	%prec UP	{ move(FWD, $1, $2); }
+	| up box	%prec UP	{ move(UP, $1, $2); }
+	| back box	%prec UP	{ move(BACK, $1, $2); }
+	| down box	%prec UP	{ move(DOWN, $1, $2); }
+	| column			{ pile($1); ct = $1; }
+	| MATRIX {$$=ct;} '{' collist '}'	{ matrix($2); ct = $2; }
+	;
+
+int	: INT		{ setintegral(); }
+	;
+
+fwd	: FWD text	{ $$ = atoi((char *) $1); } ;
+up	: UP text	{ $$ = atoi((char *) $1); } ;
+back	: BACK text	{ $$ = atoi((char *) $1); } ;
+down	: DOWN text	{ $$ = atoi((char *) $1); } ;
+
+diacrit	: HAT		{ $$ = HAT; }
+	| VEC		{ $$ = VEC; }
+	| DYAD		{ $$ = DYAD; }
+	| BAR		{ $$ = BAR; }
+	| LOWBAR	{ $$ = LOWBAR; }
+	| HIGHBAR	{ $$ = HIGHBAR; }
+	| UNDER		{ $$ = UNDER; }	/* underbar */
+	| DOT		{ $$ = DOT; }
+	| TILDE		{ $$ = TILDE; }
+	| UTILDE	{ $$ = UTILDE; }
+	| DOTDOT	{ $$ = DOTDOT; } /* umlaut = double dot */
+	;
+
+left	: LEFT text	{ $$ = ((char *)$2)[0]; }
+	| LEFT '{'	{ $$ = '{'; }
+	;
+
+right	: RIGHT text	{ $$ = ((char *)$2)[0]; }
+	| RIGHT '}'	{ $$ = '}'; }
+	;
+
+collist	: column
+	| collist column
+	;
+
+column	: col '{' list '}'				{ column($1, DEFGAP); }
+	| col text {$$=atoi((char*)$2);} '{' list '}'	{ column($1, $3); }
+	;
+
+col	: LCOL		{ $$ = startcol(LCOL); }
+	| CCOL		{ $$ = startcol(CCOL); }
+	| RCOL		{ $$ = startcol(RCOL); }
+	| COL		{ $$ = startcol(COL); }
+	;
+
+list	: eqn			{ lp[ct++] = $1; }
+	| list ABOVE eqn	{ lp[ct++] = $3; }
+	;
+
+size	: SIZE text	{ $$ = ps; setsize((char *) $2); }
+	;
+
+font    : ROMAN         { static char R[]="R"; setfont(R); }
+        | ITALIC        { static char I[]="I"; setfont(I); }
+        | BOLD          { static char B[]="B"; setfont(B); }
+        | FONT text     { setfont((char *)$2); }
+        ;
+
+text	: CONTIG
+	| QTEXT
+	;
+
+%%
diff --git a/src/cmd/eqn/eqnbox.c b/src/cmd/eqn/eqnbox.c
new file mode 100644
index 00000000..7dd0b867
--- /dev/null
+++ b/src/cmd/eqn/eqnbox.c
@@ -0,0 +1,24 @@
+#include "e.h"
+
+void eqnbox(int p1, int p2, int lu)
+{
+	double b, h;
+	char *sh;
+	extern char *IRspace;
+
+	yyval = p1;
+	b = max(ebase[p1], ebase[p2]);
+	eht[yyval] = h = b + max(eht[p1]-ebase[p1], 
+		eht[p2]-ebase[p2]);
+	ebase[yyval] = b;
+	dprintf(".\tS%d <- %d %d; b=%g, h=%g\n", yyval, p1, p2, b, h);
+	sh = pad(class[rclass[p1]][lclass[p2]]);
+	if (lu) {
+		printf(".nr %d \\w'\\*(%d%s'\n", p1, p1, sh);
+		printf(".ds %d \\h'|\\n(09u-\\n(%du'\\*(%d\n", p1, p1, p1);
+	}
+	printf(".as %d \"%s\\*(%d\n", yyval, sh, p2);
+	rfont[p1] = rfont[p2];
+	rclass[p1] = rclass[p2];
+	sfree(p2);
+}
diff --git a/src/cmd/eqn/font.c b/src/cmd/eqn/font.c
new file mode 100644
index 00000000..3fb01119
--- /dev/null
+++ b/src/cmd/eqn/font.c
@@ -0,0 +1,70 @@
+# include "e.h"
+
+void setfont(char *ch1)
+{
+	yyval = ft;
+	if (strcmp(ch1, "I") == 0) {	/* I and italic mean merely position 2 */
+		*ch1 = '2';
+		ft = ITAL;
+	} else if (strcmp(ch1, "B") == 0) {	/* and similarly for B & bold */
+		*ch1 = '3';
+		ft = BLD;
+	} else if (strcmp(ch1, "R") == 0) {	/* and R and roman */
+		*ch1 = '1';
+		ft = ROM;
+	} else {
+		ft = ROM;	/* assume it's a roman style */
+	}
+	ftp++;
+	if (ftp >= &ftstack[10])
+		ERROR "font stack overflow (10)" FATAL;
+	ftp->ft = ft;
+	if (ch1[1] == 0) {	/* 1-char name */
+		ftp->name[0] = *ch1;
+		ftp->name[1] = '\0';
+	} else
+		sprintf(ftp->name, "(%s", ch1);
+	dprintf(".\tsetfont %s %c\n", ch1, ft);
+}
+
+void font(int p1, int p2)
+{
+		/* old font in p1, new in ft */
+	yyval = p2;
+	lfont[yyval] = rfont[yyval] = ft==ITAL ? ITAL : ROM;
+	ftp--;
+	ft = p1;
+}
+
+void globfont(void)
+{
+	char temp[20];
+
+	getstr(temp, sizeof(temp));
+	yyval = eqnreg = 0;
+	if (strcmp(temp, "I") == 0 || strncmp(temp, "it", 2) == 0) {
+		ft = ITAL;
+		strcpy(temp, "2");
+	} else if (strcmp(temp, "B") == 0 || strncmp(temp, "bo", 2) == 0) {
+		ft = BLD;
+		strcpy(temp, "3");
+	} else if (strcmp(temp, "R") == 0 || strncmp(temp, "ro", 2) == 0) {
+		ft = ROM;
+		strcpy(temp, "1");
+	} else { 
+		ft = ROM;	/* assume it's a roman style */
+	}
+	ftstack[0].ft = ft;
+	if (temp[1] == 0)	/* 1-char name */
+		strcpy(ftstack[0].name, temp);
+	else
+		sprintf(ftstack[0].name, "(%.2s", temp);
+}
+
+void fatbox(int p)
+{
+	extern double Fatshift;
+
+	yyval = p;
+	printf(".ds %d \\*(%d\\h'-\\w'\\*(%d'u+%gm'\\*(%d\n", p, p, p, Fatshift, p);
+}
diff --git a/src/cmd/eqn/fromto.c b/src/cmd/eqn/fromto.c
new file mode 100644
index 00000000..2d4d7f74
--- /dev/null
+++ b/src/cmd/eqn/fromto.c
@@ -0,0 +1,52 @@
+# include "e.h"
+
+void fromto(int p1, int p2, int p3)
+{
+	double b, h1, b1, t;
+	int subps;
+
+	yyval = salloc();
+	lfont[yyval] = rfont[yyval] = 0;
+	h1 = eht[yyval] = eht[p1];
+	b1 = ebase[p1];
+	b = 0;
+	subps = ps;
+	ps += deltaps;
+	nrwid(p1, ps, p1);
+	printf(".nr %d \\n(%d\n", yyval, p1);
+	if (p2 > 0) {
+		nrwid(p2, subps, p2);
+		printf(".if \\n(%d>\\n(%d .nr %d \\n(%d\n", p2, yyval, yyval, p2);
+		eht[yyval] += eht[p2];
+		b = eht[p2];
+	}
+	if (p3 > 0) {
+		nrwid(p3, subps, p3);
+		printf(".if \\n(%d>\\n(%d .nr %d \\n(%d\n", p3, yyval, yyval, p3);
+		eht[yyval] += eht[p3];
+	}
+	printf(".ds %d ", yyval);	/* bottom of middle box */
+	if (p2 > 0) {
+		t = eht[p2]-ebase[p2]+b1;
+		printf("\\v'%gm'\\h'\\n(%du-\\n(%du/2u'%s\\*(%d%s", 
+			REL(t,ps), yyval, p2, DPS(ps,subps), p2, DPS(subps,ps));
+		printf("\\h'-\\n(%du-\\n(%du/2u'\\v'%gm'\\\n", 
+			yyval, p2, REL(-t,ps));
+	}
+	printf("\\h'\\n(%du-\\n(%du/2u'\\*(%d\\h'\\n(%du-\\n(%du/2u'\\\n", 
+		yyval, p1, p1, yyval, p1);
+	if (p3  >0) {
+		t = h1-b1+ebase[p3];
+		printf("\\v'%gm'\\h'-\\n(%du-\\n(%du/2u'%s\\*(%d%s\\h'\\n(%du-\\n(%du/2u'\\v'%gm'\\\n", 
+			REL(-t,ps), yyval, p3, DPS(ps,subps), p3, DPS(subps,ps), yyval, p3, REL(t,ps));
+	}
+	printf("\n");
+	ebase[yyval] = b + b1;
+	dprintf(".\tS%d <- %d from %d to %d; h=%g b=%g\n", 
+		yyval, p1, p2, p3, eht[yyval], ebase[yyval]);
+	sfree(p1);
+	if (p2 > 0)
+		sfree(p2);
+	if (p3 > 0)
+		sfree(p3);
+}
diff --git a/src/cmd/eqn/funny.c b/src/cmd/eqn/funny.c
new file mode 100644
index 00000000..85955fce
--- /dev/null
+++ b/src/cmd/eqn/funny.c
@@ -0,0 +1,30 @@
+#include "e.h"
+#include "y.tab.h"
+
+extern int Funnyps;
+extern double Funnyht, Funnybase;
+
+void funny(int n)
+{
+	char *f = 0;
+
+	yyval = salloc();
+	switch (n) {
+	case SUM:
+		f = lookup(deftbl, "sum_def")->cval; break;
+	case UNION:
+		f = lookup(deftbl, "union_def")->cval; break;
+	case INTER:	/* intersection */
+		f = lookup(deftbl, "inter_def")->cval; break;
+	case PROD:
+		f = lookup(deftbl, "prod_def")->cval; break;
+	default:
+		ERROR "funny type %d in funny", n FATAL;
+	}
+	printf(".ds %d %s\n", yyval, f);
+	eht[yyval] = EM(1.0, ps+Funnyps) - EM(Funnyht, ps);
+	ebase[yyval] = EM(Funnybase, ps);
+	dprintf(".\tS%d <- %s; h=%g b=%g\n", 
+		yyval, f, eht[yyval], ebase[yyval]);
+	lfont[yyval] = rfont[yyval] = ROM;
+}
diff --git a/src/cmd/eqn/glob.c b/src/cmd/eqn/glob.c
new file mode 100644
index 00000000..6ca1a1da
--- /dev/null
+++ b/src/cmd/eqn/glob.c
@@ -0,0 +1,35 @@
+#include "e.h"
+
+	/* YOU MAY WANT TO CHANGE THIS */
+char	*typesetter = "post";	/* type of typesetter today */
+int	ttype	= DEVPOST;
+int	minsize	= 4;		/* min size it can handle */
+
+
+int	dbg;		/* debugging print if non-zero */
+int	lp[200];	/* stack for things like piles and matrices */
+int	ct;		/* pointer to lp */
+int	used[100];	/* available registers */
+int	ps;		/* default init point size */
+int	deltaps	= 3;	/* default change in ps */
+int	dps_set = 0;	/* 1 => -p option used */
+int	gsize	= 10;	/* default initial point size */
+int	ft	= '2';
+Font	ftstack[10] = { '2', "2" };	/* bottom is global font */
+Font	*ftp	= ftstack;
+int	szstack[10];	/* non-zero if absolute size set at this level */
+int	nszstack = 0;
+int	display	= 0;	/* 1=>display, 0=>.EQ/.EN */
+
+int	synerr;		/* 1 if syntax err in this eqn */
+double	eht[100];	/* height in ems at gsize */
+double	ebase[100];	/* base: where one enters above bottom */
+int	lfont[100];	/* leftmost and rightmost font associated with this thing */
+int	rfont[100];
+int	lclass[100];	/* leftmost and rightmost class associated with this thing */
+int	rclass[100];
+int	eqnreg;		/* register where final string appears */
+double	eqnht;		/* final height of equation */
+int	lefteq	= '\0';	/* left in-line delimiter */
+int	righteq	= '\0';	/* right in-line delimiter */
+int	markline = 0;	/* 1 if this EQ/EN contains mark; 2 if lineup */
diff --git a/src/cmd/eqn/input.c b/src/cmd/eqn/input.c
new file mode 100644
index 00000000..3b865671
--- /dev/null
+++ b/src/cmd/eqn/input.c
@@ -0,0 +1,289 @@
+#include "e.h"
+#include "y.tab.h"
+#include <ctype.h>
+#include <errno.h>
+
+Infile	infile[10];
+Infile	*curfile = infile;
+
+#define	MAXSRC	50
+Src	src[MAXSRC];	/* input source stack */
+Src	*srcp	= src;
+
+extern int getarg(char *);
+extern	void eprint(void);
+
+void pushsrc(int type, char *ptr)	/* new input source */
+{
+	if (++srcp >= src + MAXSRC)
+		ERROR "inputs nested too deep" FATAL;
+	srcp->type = type;
+	srcp->sp = ptr;
+	if (dbg > 1) {
+		printf("\n%3d ", srcp - src);
+		switch (srcp->type) {
+		case File:
+			printf("push file %s\n", ((Infile *)ptr)->fname);
+			break;
+		case Macro:
+			printf("push macro <%s>\n", ptr);
+			break;
+		case Char:
+			printf("push char <%c>\n", *ptr);
+			break;
+		case String:
+			printf("push string <%s>\n", ptr);
+			break;
+		case Free:
+			printf("push free <%s>\n", ptr);
+			break;
+		default:
+			ERROR "pushed bad type %d\n", srcp->type FATAL;
+		}
+	}
+}
+
+void popsrc(void)	/* restore an old one */
+{
+	if (srcp <= src)
+		ERROR "too many inputs popped" FATAL;
+	if (dbg > 1) {
+		printf("%3d ", srcp - src);
+		switch (srcp->type) {
+		case File:
+			printf("pop file\n");
+			break;
+		case Macro:
+			printf("pop macro\n");
+			break;
+		case Char:
+			printf("pop char <%c>\n", *srcp->sp);
+			break;
+		case String:
+			printf("pop string\n");
+			break;
+		case Free:
+			printf("pop free\n");
+			break;
+		default:
+			ERROR "pop weird input %d\n", srcp->type FATAL;
+		}
+	}
+	srcp--;
+}
+
+Arg	args[10];	/* argument frames */
+Arg	*argfp = args;	/* frame pointer */
+int	argcnt;		/* number of arguments seen so far */
+
+void dodef(tbl *stp)	/* collect args and switch input to defn */
+{
+	int i, len;
+	char *p;
+	Arg *ap;
+
+	ap = argfp+1;
+	if (ap >= args+10)
+		ERROR "more than arguments\n" FATAL;
+	argcnt = 0;
+	if (input() != '(')
+		ERROR "disaster in dodef\n"FATAL;
+	if (ap->argval == 0)
+		ap->argval = malloc(1000);
+	for (p = ap->argval; (len = getarg(p)) != -1; p += len) {
+		ap->argstk[argcnt++] = p;
+		if (input() == ')')
+			break;
+	}
+	for (i = argcnt; i < MAXARGS; i++)
+		ap->argstk[i] = "";
+	if (dbg)
+		for (i = 0; i < argcnt; i++)
+			printf("arg %d.%d = <%s>\n", ap-args, i+1, ap->argstk[i]);
+	argfp = ap;
+	pushsrc(Macro, stp->cval);
+}
+
+getarg(char *p)	/* pick up single argument, store in p, return length */
+{
+	int n, c, npar;
+
+	n = npar = 0;
+	for ( ;; ) {
+		c = input();
+		if (c == EOF)
+			ERROR "end of file in getarg!\n" FATAL;
+		if (npar == 0 && (c == ',' || c == ')'))
+			break;
+		if (c == '"')	/* copy quoted stuff intact */
+			do {
+				*p++ = c;
+				n++;
+			} while ((c = input()) != '"' && c != EOF);
+		else if (c == '(')
+			npar++;
+		else if (c == ')')
+			npar--;
+		n++;
+		*p++ = c;
+	}
+	*p = 0;
+	unput(c);
+	return(n + 1);
+}
+
+#define	PBSIZE	2000
+char	pbuf[PBSIZE];		/* pushback buffer */
+char	*pb	= pbuf-1;	/* next pushed back character */
+
+char	ebuf[200];		/* collect input here for error reporting */
+char	*ep	= ebuf;
+
+input(void)
+{
+	register int c = 0;
+
+  loop:
+	switch (srcp->type) {
+	case File:
+		c = getc(curfile->fin);
+		if (c == EOF) {
+			if (curfile == infile)
+				break;
+			if (curfile->fin != stdin) {
+				fclose(curfile->fin);
+				free(curfile->fname);	/* assumes allocated */
+			}
+			curfile--;
+			printf(".lf %d %s\n", curfile->lineno, curfile->fname);
+			popsrc();
+			goto loop;
+		}
+		if (c == '\n')
+			curfile->lineno++;
+		break;
+	case Char:
+		if (pb >= pbuf) {
+			c = *pb--;
+			popsrc();
+			break;
+		} else {	/* can't happen? */
+			popsrc();
+			goto loop;
+		}
+	case String:
+		c = *srcp->sp++;
+		if (c == '\0') {
+			popsrc();
+			goto loop;
+		} else {
+			if (*srcp->sp == '\0')	/* empty, so pop */
+				popsrc();
+			break;
+		}
+	case Macro:
+		c = *srcp->sp++;
+		if (c == '\0') {
+			if (--argfp < args)
+				ERROR "argfp underflow" FATAL;
+			popsrc();
+			goto loop;
+		} else if (c == '$' && isdigit(*srcp->sp)) {
+			int n = 0;
+			while (isdigit(*srcp->sp))
+				n = 10 * n + *srcp->sp++ - '0';
+			if (n > 0 && n <= MAXARGS)
+				pushsrc(String, argfp->argstk[n-1]);
+			goto loop;
+		}
+		break;
+	case Free:	/* free string */
+		free(srcp->sp);
+		popsrc();
+		goto loop;
+	}
+	if (ep >= ebuf + sizeof ebuf)
+		ep = ebuf;
+	*ep++ = c;
+	return c;
+}
+
+
+unput(int c)
+{
+	if (++pb >= pbuf + sizeof pbuf)
+		ERROR "pushback overflow\n"FATAL;
+	if (--ep < ebuf)
+		ep = ebuf + sizeof(ebuf) - 1;
+	*pb = c;
+	pushsrc(Char, pb);
+	return c;
+}
+
+void pbstr(char *s)
+{
+	pushsrc(String, s);
+}
+
+void error(int die, char *s)
+{
+	extern char *cmdname;
+
+	if (synerr)
+		return;
+	fprintf(stderr, "%s: ", cmdname);
+	fprintf(stderr, s);
+	if (errno > 0)
+		perror("???");
+	if (curfile->fin)
+		fprintf(stderr, " near %s:%d",
+			curfile->fname, curfile->lineno+1);
+	fprintf(stderr, "\n");
+	eprint();
+	synerr = 1;
+	errno = 0;
+	if (die) {
+		if (dbg)
+			abort();
+		else
+			exit(1);
+	}
+}
+
+void yyerror(char *s)
+{
+	error(0, s);	/* temporary */
+}
+
+char errbuf[200];
+
+void eprint(void)	/* try to print context around error */
+{
+	char *p, *q;
+
+	if (ep == ebuf)
+		return;				/* no context */
+	p = ep - 1;
+	if (p > ebuf && *p == '\n')
+		p--;
+	for ( ; p >= ebuf && *p != '\n'; p--)
+		;
+	while (*p == '\n')
+		p++;
+	fprintf(stderr, " context is\n\t");
+	for (q=ep-1; q>=p && *q!=' ' && *q!='\t' && *q!='\n'; q--)
+		;
+	while (p < q)
+		putc(*p++, stderr);
+	fprintf(stderr, " >>> ");
+	while (p < ep)
+		putc(*p++, stderr);
+	fprintf(stderr, " <<< ");
+	while (pb >= pbuf)
+		putc(*pb--, stderr);
+	if (curfile->fin)
+		fgets(ebuf, sizeof ebuf, curfile->fin);
+	fprintf(stderr, "%s", ebuf);
+	pbstr("\n.EN\n");	/* safety first */
+	ep = ebuf;
+}
diff --git a/src/cmd/eqn/integral.c b/src/cmd/eqn/integral.c
new file mode 100644
index 00000000..2b1c9e3f
--- /dev/null
+++ b/src/cmd/eqn/integral.c
@@ -0,0 +1,30 @@
+#include "e.h"
+#include "y.tab.h"
+
+extern int Intps;
+extern double Intht, Intbase, Int1h, Int1v, Int2h, Int2v;
+
+void integral(int p, int p1, int p2)
+{
+	if (p1 != 0)
+		printf(".ds %d \\h'%gm'\\v'%gm'\\*(%d\\v'%gm'\n", p1, -Int1h, Int1v, p1, -Int1v);
+	if (p2 != 0)
+		printf(".ds %d \\v'%gm'\\h'%gm'\\*(%d\\v'%gm'\n", p2, -Int2v, Int2h, p2, Int2v);
+	if (p1 != 0 && p2 != 0)
+		shift2(p, p1, p2);
+	else if (p1 != 0)
+		bshiftb(p, SUB, p1);
+	else if (p2 != 0)
+		bshiftb(p, SUP, p2);
+	dprintf(".\tintegral: S%d; h=%g b=%g\n", p, eht[p], ebase[p]);
+	lfont[p] = ROM;
+}
+
+void setintegral(void)
+{
+	yyval = salloc();
+	printf(".ds %d %s\n", yyval, lookup(deftbl, "int_def")->cval);
+	eht[yyval] = EM(Intht, ps+Intps);
+	ebase[yyval] = EM(Intbase, ps);
+	lfont[yyval] = rfont[yyval] = ROM;
+}
diff --git a/src/cmd/eqn/lex.c b/src/cmd/eqn/lex.c
new file mode 100644
index 00000000..e535b869
--- /dev/null
+++ b/src/cmd/eqn/lex.c
@@ -0,0 +1,265 @@
+#include "e.h"
+#include "y.tab.h"
+#include <ctype.h>
+
+#define	SSIZE	1000
+char	token[SSIZE];
+int	sp;
+
+void	space(void);
+void	dodef(tbl *);
+void	define(int);
+void	ifdef(void);
+void	include(void);
+void	delim(void);
+
+yylex(void)
+{
+	register int c;
+	tbl *tp;
+
+  begin:
+	while ((c = input()) == ' ' || c == '\n' || c == '\t')
+		;
+	yylval = c;
+	switch (c) {
+	case EOF:
+		ERROR "unexpected end of input inside equation" WARNING;
+		return(EOF);
+	case '~':
+		return(SPACE);
+	case '^':
+		return(THIN);
+	/* case '\t':
+		return(TAB);
+	*/
+	case '{':
+		return('{');
+	case '}':
+		return('}');
+	case '"':
+		for (sp = 0; (c=input())!='"' && c != '\n'; ) {
+			if (c == '\\')
+				if ((c = input()) != '"')
+					token[sp++] = '\\';
+			token[sp++] = c;
+			if (sp >= SSIZE)
+				ERROR "quoted string %.20s... too long", token FATAL;
+		}
+		token[sp] = '\0';
+		yylval = (int) &token[0];
+		if (c == '\n')
+			ERROR "missing \" in %.20s", token WARNING;
+		return(QTEXT);
+	}
+	if (!display && c == righteq)
+		return(EOF);
+
+	unput(c);
+	getstr(token, SSIZE);
+	dprintf(".\tlex token = |%s|\n", token);
+	if ((tp = lookup(deftbl, token)) != NULL) {	/* defined term */
+		c = input();
+		unput(c);
+		if (c == '(')	/* macro with args */
+			dodef(tp);
+		else {		/* no args */
+			unput(' ');
+			pbstr(tp->cval);
+			dprintf(".\tfound %s|=%s|\n", token, tp->cval);
+		}
+		goto begin;
+	}
+
+	if ((tp = lookup(keytbl, token)) == NULL)	/* not a keyword */
+		return CONTIG;
+
+	switch (tp->ival) {		/* some kind of keyword */
+	case DEFINE: case TDEFINE: case NDEFINE:
+		define(tp->ival);
+		break;
+	case IFDEF:
+		ifdef();
+		break;
+	case DELIM:
+		delim();
+		break;
+	case GSIZE:
+		globsize();
+		break;
+	case GFONT:
+		globfont();
+		break;
+	case INCLUDE:
+		include();
+		break;
+	case SPACE:
+		space();
+		break;
+	case DOTEQ:
+			/* .EQ inside equation -- should warn if at bottom level */
+		break;
+	case DOTEN:
+		if (curfile == infile)
+			return EOF;
+		/* else ignore nested .EN */
+		break;
+	default:
+		return tp->ival;
+	}
+	goto begin;
+}
+
+void getstr(char *s, int n)
+{
+	register int c;
+	register char *p;
+
+	p = s;
+	while ((c = input()) == ' ' || c == '\n')
+		;
+	if (c == EOF) {
+		*s = 0;
+		return;
+	}
+	while (c != ' ' && c != '\t' && c != '\n' && c != '{' && c != '}'
+	    && c != '"' && c != '~' && c != '^') {
+		if (!display && c == righteq)
+			break;
+		if (c == '(' && p > s) {	/* might be defined(...) */
+			*p = '\0';
+			if (lookup(deftbl, s) != NULL)
+				break;
+		}
+		if (c == '\\')
+			if ((c = input()) != '"')
+				*p++ = '\\';
+		*p++ = c;
+		if (--n <= 0)
+			ERROR "token %.20s... too long", s FATAL;
+		c = input();
+	}
+	unput(c);
+	*p = '\0';
+	yylval = (int) s;
+}
+
+cstr(char *s, int quote, int maxs)
+{
+	int del, c, i;
+
+	s[0] = 0;
+	while ((del=input()) == ' ' || del == '\t')
+		;
+	if (quote)
+		for (i=0; (c=input()) != del && c != EOF;) {
+			s[i++] = c;
+			if (i >= maxs)
+				return(1);	/* disaster */
+		}
+	else {
+		if (del == '\n')
+			return(1);
+		s[0] = del;
+		for (i=1; (c=input())!=' ' && c!= '\t' && c!='\n' && c!=EOF;) {
+			s[i++] = c;
+			if (i >= maxs)
+				return(1);	/* disaster */
+		}
+	}
+	s[i] = '\0';
+	if (c == EOF)
+		ERROR "Unexpected end of input at %.20s", s FATAL;
+	return(0);
+}
+
+void define(int type)
+{
+	char *p1, *p2;
+	extern int ftune(char *, char *);
+
+	getstr(token, SSIZE);	/* get name */
+	if (type != DEFINE) {
+		cstr(token, 1, SSIZE);	/* skip the definition too */
+		return;
+	}
+	p1 = strsave(token);
+	if (cstr(token, 1, SSIZE))
+		ERROR "Unterminated definition at %.20s", token FATAL;
+	if (lookup(ftunetbl, p1) != NULL) {	/* double tuning param */
+		dprintf(".\ttune %s %s\n", p1, token);
+		ftune(p1, token);
+	} else {
+		p2 = strsave(token);
+		install(deftbl, p1, p2, 0);
+		dprintf(".\tname %s defined as %s\n", p1, p2);
+	}
+}
+
+void ifdef(void)		/* do body if name is defined */
+{
+	char name[100], *p;
+
+	getstr(name, sizeof(name));	/* get name */
+	cstr(token, 1, SSIZE);		/* and body */
+	if (lookup(deftbl, name) != NULL) {	/* found it */
+		p = strsave(token);
+		pushsrc(Free, p);
+		pushsrc(String, p);
+	}
+}
+
+char	*spaceval	= NULL;
+
+void space(void)	/* collect line of form "space amt" to replace \x in output */
+{
+	getstr(token, SSIZE);
+	spaceval = strsave(token);
+	dprintf(".\tsetting spaceval to %s\n", token);
+}
+
+char *strsave(char *s)
+{
+	register char *q;
+
+	q = malloc(strlen(s)+1);
+	if (q == NULL)
+		ERROR "out of space in strsave on %s", s FATAL;
+	strcpy(q, s);
+	return(q);
+}
+
+void include(void)
+{
+	char name[100];
+	FILE *fin;
+	int c;
+	extern int errno;
+
+	while ((c = input()) == ' ')
+		;
+	unput(c);
+	cstr(name, c == '"', sizeof(name));	/* gets it quoted or not */
+	if ((fin = fopen(name, "r")) == NULL)
+		ERROR "can't open file %s", name FATAL;
+	errno = 0;
+	curfile++;
+	curfile->fin = fin;
+	curfile->fname = strsave(name);
+	curfile->lineno = 0;
+	printf(".lf 1 %s\n", curfile->fname);
+	pushsrc(File, curfile->fname);
+}
+
+void delim(void)
+{
+	yyval = eqnreg = 0;
+	if (cstr(token, 0, SSIZE))
+		ERROR "Bizarre delimiters" FATAL;
+	lefteq = token[0];
+	righteq = token[1];
+        if (!isprint(lefteq) || !isprint(righteq))
+		ERROR "Bizarre delimiters" FATAL;
+	if (lefteq == 'o' && righteq == 'f')
+		lefteq = righteq = '\0';
+}
diff --git a/src/cmd/eqn/lookup.c b/src/cmd/eqn/lookup.c
new file mode 100644
index 00000000..4eb94373
--- /dev/null
+++ b/src/cmd/eqn/lookup.c
@@ -0,0 +1,219 @@
+#include "e.h"
+#include "y.tab.h"
+
+tbl	*keytbl[TBLSIZE];	/* key words */
+tbl	*restbl[TBLSIZE];	/* reserved words */
+tbl	*deftbl[TBLSIZE];	/* user-defined names */
+
+struct keyword {
+	char	*key;
+	int	keyval;
+} keyword[]	={
+	"sub", 		SUB, 
+	"sup", 		SUP, 
+	".EN", 		DOTEN,
+	".EQ",		DOTEQ, 
+	"from", 	FROM, 
+	"to", 		TO, 
+	"sum", 		SUM, 
+	"hat", 		HAT, 
+	"vec", 		VEC, 
+	"dyad", 	DYAD, 
+	"dot", 		DOT, 
+	"dotdot", 	DOTDOT, 
+	"bar", 		BAR,
+	"lowbar",	LOWBAR,
+	"highbar",	HIGHBAR, 
+	"tilde", 	TILDE, 
+	"utilde", 	UTILDE, 
+	"under", 	UNDER, 
+	"prod", 	PROD, 
+	"int", 		INT, 
+	"integral", 	INT, 
+	"union", 	UNION, 
+	"inter", 	INTER, 
+	"matrix", 	MATRIX, 
+	"col", 		COL, 
+	"lcol", 	LCOL, 
+	"ccol", 	CCOL, 
+	"rcol", 	RCOL, 
+	"pile", 	COL,	/* synonyms ... */ 
+	"lpile", 	LCOL, 
+	"cpile", 	CCOL, 
+	"rpile", 	RCOL, 
+	"over", 	OVER, 
+	"sqrt", 	SQRT, 
+	"above", 	ABOVE, 
+	"size", 	SIZE, 
+	"font", 	FONT, 
+	"fat", 		FAT, 
+	"roman", 	ROMAN, 
+	"italic", 	ITALIC, 
+	"bold", 	BOLD, 
+	"left", 	LEFT, 
+	"right", 	RIGHT, 
+	"delim", 	DELIM, 
+	"define", 	DEFINE, 
+	"tdefine", 	DEFINE, 
+	"ndefine", 	NDEFINE, 
+	"ifdef",	IFDEF,
+	"gsize", 	GSIZE, 
+	".gsize", 	GSIZE, 
+	"gfont", 	GFONT, 
+	"include", 	INCLUDE, 
+	"copy", 	INCLUDE, 
+	"space",	SPACE,
+	"up", 		UP, 
+	"down", 	DOWN, 
+	"fwd", 		FWD, 
+	"back", 	BACK, 
+	"mark", 	MARK, 
+	"lineup", 	LINEUP, 
+	0, 	0
+};
+
+struct resword {
+	char	*res;
+	char	*resval;
+} resword[]	={
+	">=",		"\\(>=",
+	"<=",		"\\(<=",
+	"==",		"\\(==",
+	"!=",		"\\(!=",
+	"+-",		"\\(+-",
+	"->",		"\\(->",
+	"<-",		"\\(<-",
+	"inf",		"\\(if",
+	"infinity",	"\\(if",
+	"partial",	"\\(pd",
+	"half",		"\\f1\\(12\\fP",
+	"prime",	"\\f1\\v'.5m'\\s+3\\(fm\\s-3\\v'-.5m'\\fP",
+	"dollar",	"\\f1$\\fP",
+	"nothing",	"",
+	"times",	"\\(mu",
+	"del",		"\\(gr",
+	"grad",		"\\(gr",
+	"approx",	"\\v'-.2m'\\z\\(ap\\v'.25m'\\(ap\\v'-.05m'",
+	"cdot",		"\\v'-.3m'.\\v'.3m'",
+	"...",		"\\v'-.25m'\\ .\\ .\\ .\\ \\v'.25m'",
+	",...,",	"\\f1,\\fP\\ .\\ .\\ .\\ \\f1,\\fP\\|",
+	"alpha",	"α",
+	"ALPHA",	"Α",
+	"beta",		"β",
+	"BETA",		"Β",
+	"gamma",	"γ",
+	"GAMMA",	"Γ",
+	"delta",	"δ",
+	"DELTA",	"Δ",
+	"epsilon",	"ε",
+	"EPSILON",	"Ε",
+	"omega",	"ω",
+	"OMEGA",	"Ω",
+	"lambda",	"λ",
+	"LAMBDA",	"Λ",
+	"mu",		"μ",
+	"MU",		"Μ",
+	"nu",		"ν",
+	"NU",		"Ν",
+	"theta",	"θ",
+	"THETA",	"Θ",
+	"phi",		"φ",
+	"PHI",		"Φ",
+	"pi",		"π",
+	"PI",		"Π",
+	"sigma",	"σ",
+	"SIGMA",	"Σ",
+	"xi",		"ξ",
+	"XI",		"Ξ",
+	"zeta",		"ζ",
+	"ZETA",		"Ζ",
+	"iota",		"ι",
+	"IOTA",		"Ι",
+	"eta",		"η",
+	"ETA",		"Η",
+	"kappa",	"κ",
+	"KAPPA",	"Κ",
+	"rho",		"ρ",
+	"RHO",		"Ρ",
+	"tau",		"τ",
+	"TAU",		"Τ",
+	"omicron",	"ο",
+	"OMICRON",	"Ο",
+	"upsilon",	"υ",
+	"UPSILON",	"Υ",
+	"psi",		"ψ",
+	"PSI",		"Ψ",
+	"chi",		"χ",
+	"CHI",		"Χ",
+	"and",		"\\f1and\\fP",
+	"for",		"\\f1for\\fP",
+	"if",		"\\f1if\\fP",
+	"Re",		"\\f1Re\\fP",
+	"Im",		"\\f1Im\\fP",
+	"sin",		"\\f1sin\\fP",
+	"cos",		"\\f1cos\\fP",
+	"tan",		"\\f1tan\\fP",
+	"arc",		"\\f1arc\\fP",
+	"sinh",		"\\f1sinh\\fP",
+	"coth",		"\\f1coth\\fP",
+	"tanh",		"\\f1tanh\\fP",
+	"cosh",		"\\f1cosh\\fP",
+	"lim",		"\\f1lim\\fP",
+	"log",		"\\f1log\\fP",
+	"ln",		"\\f1ln\\fP",
+	"max",		"\\f1max\\fP",
+	"min",		"\\f1min\\fP",
+	"exp",		"\\f1exp\\fP",
+	"det",		"\\f1det\\fP",
+	0,	0
+};
+
+int hash(char *s)
+{
+	register unsigned int h;
+
+	for (h = 0; *s != '\0'; )
+		h += *s++;
+	h %= TBLSIZE;
+	return h;
+}
+
+tbl *lookup(tbl **tblp, char *name)	/* find name in tbl */
+{
+	register tbl *p;
+
+	for (p = tblp[hash(name)]; p != NULL; p = p->next)
+		if (strcmp(name, p->name) == 0)
+			return(p);
+	return(NULL);
+}
+
+void install(tbl **tblp, char *name, char *cval, int ival)	/* install name, vals in tblp */
+{
+	register tbl *p;
+	int h;
+
+	if ((p = lookup(tblp, name)) == NULL) {
+		p = (tbl *) malloc(sizeof(tbl));
+		if (p == NULL)
+			ERROR "out of space in install" FATAL;
+		h = hash(name);	/* bad visibility here */
+		p->name = name;
+		p->next = tblp[h];
+		tblp[h] = p;
+	}
+	p->cval = cval;
+	p->ival = ival;
+}
+
+void init_tbl(void)	/* initialize tables */
+{
+	int i;
+	extern int init_tune(void);
+
+	for (i = 0; keyword[i].key != NULL; i++)
+		install(keytbl, keyword[i].key, (char *) 0, keyword[i].keyval);
+	for (i = 0; resword[i].res != NULL; i++)
+		install(restbl, resword[i].res, resword[i].resval, 0);
+	init_tune();	/* tuning table done in tuning.c */
+}
diff --git a/src/cmd/eqn/main.c b/src/cmd/eqn/main.c
new file mode 100644
index 00000000..a06fd165
--- /dev/null
+++ b/src/cmd/eqn/main.c
@@ -0,0 +1,333 @@
+#include "e.h"
+
+#define	MAXLINE	3600	/* maximum input line */
+
+char *version = "version Oct 24, 1991";
+
+char	in[MAXLINE];	/* input buffer */
+int	noeqn;
+char	*cmdname;
+
+int	yyparse(void);
+void	settype(char *);
+int	getdata(void);
+int	getline(char *);
+#define inline einline
+void	inline(void);
+void	init(void);
+void	init_tbl(void);
+
+void
+main(int argc, char *argv[])
+{
+	char *p, buf[20];
+
+	cmdname = argv[0];
+	if (p = getenv("TYPESETTER"))
+		typesetter = p;
+	while (argc > 1 && argv[1][0] == '-') {
+		switch (argv[1][1]) {
+
+		case 'd':
+			if (argv[1][2] == '\0') {
+				dbg++;
+				printf("...\teqn %s\n", version);
+			} else {
+				lefteq = argv[1][2];
+				righteq = argv[1][3];
+			}
+			break;
+		case 's': szstack[0] = gsize = atoi(&argv[1][2]); break;
+		case 'p': deltaps = atoi(&argv[1][2]); dps_set = 1; break;
+		case 'm': minsize = atoi(&argv[1][2]); break;
+		case 'f': strcpy(ftstack[0].name,&argv[1][2]); break;
+		case 'e': noeqn++; break;
+		case 'T': typesetter = &argv[1][2]; break;
+		default:
+			fprintf(stderr, "%s: unknown option %s\n", cmdname, argv[1]);
+			break;
+		}
+		argc--;
+		argv++;
+	}
+	settype(typesetter);
+	sprintf(buf, "\"%s\"", typesetter);
+	install(deftbl, strsave(typesetter), strsave(buf), 0);
+	init_tbl();	/* install other keywords in tables */
+	curfile = infile;
+	pushsrc(File, curfile->fname);
+	if (argc <= 1) {
+		curfile->fin = stdin;
+		curfile->fname = strsave("-");
+		getdata();
+	} else
+		while (argc-- > 1) {
+			if (strcmp(*++argv, "-") == 0)
+				curfile->fin = stdin;
+			else if ((curfile->fin = fopen(*argv, "r")) == NULL)
+				ERROR "can't open file %s", *argv FATAL;
+			curfile->fname = strsave(*argv);
+			getdata();
+			if (curfile->fin != stdin)
+				fclose(curfile->fin);
+		}
+	exit(0);
+}
+
+void settype(char *s)	/* initialize data for particular typesetter */
+			/* the minsize could profitably come from the */
+{			/* troff description file /usr/lib/font/dev.../DESC.out */
+	if (strcmp(s, "202") == 0)
+		{ minsize = 5; ttype = DEV202; }
+	else if (strcmp(s, "aps") == 0)
+		{ minsize = 5; ttype = DEVAPS; }
+	else if (strcmp(s, "cat") == 0)
+		{ minsize = 6; ttype = DEVCAT; }
+	else if (strcmp(s, "post") == 0)
+		{ minsize = 4; ttype = DEVPOST; }
+	else
+		{ minsize = 5; ttype = DEV202; }
+}
+
+getdata(void)
+{
+	int i, type, ln;
+	char fname[100];
+	extern int errno;
+
+	errno = 0;
+	curfile->lineno = 0;
+	printf(".lf 1 %s\n", curfile->fname);
+	while ((type = getline(in)) != EOF) {
+		if (in[0] == '.' && in[1] == 'E' && in[2] == 'Q') {
+			for (i = 11; i < 100; i++)
+				used[i] = 0;
+			printf("%s", in);
+			if (markline) {	/* turn off from last time */
+				printf(".nr MK 0\n");
+				markline = 0;
+			}
+			display = 1;
+			init();
+			yyparse();
+			if (eqnreg > 0) {
+				if (markline)
+					printf(".nr MK %d\n", markline); /* for -ms macros */
+				printf(".if %gm>\\n(.v .ne %gm\n", eqnht, eqnht);
+				printf(".rn %d 10\n", eqnreg);
+				if (!noeqn)
+					printf("\\&\\*(10\n");
+			}
+			printf(".EN");
+			while (putchar(input()) != '\n')
+				;
+			printf(".lf %d\n", curfile->lineno+1);
+		}
+		else if (type == lefteq)
+			inline();
+		else if (in[0] == '.' && in[1] == 'l' && in[2] == 'f') {
+			if (sscanf(in+3, "%d %s", &ln, fname) == 2) {
+				free(curfile->fname);
+				printf(".lf %d %s\n", curfile->lineno = ln, curfile->fname = strsave(fname));
+			} else
+				printf(".lf %d\n", curfile->lineno = ln);
+		} else
+			printf("%s", in);
+	}
+	return(0);
+}
+
+getline(char *s)
+{
+	register c;
+
+	while ((c=input()) != '\n' && c != EOF && c != lefteq) {
+		if (s >= in+MAXLINE) {
+			ERROR "input line too long: %.20s\n", in WARNING;
+			in[MAXLINE] = '\0';
+			break;
+		}
+		*s++ = c;
+	}
+	if (c != lefteq)
+		*s++ = c;
+	*s = '\0';
+	return(c);
+}
+
+void inline(void)
+{
+	int ds, n, sz1 = 0;
+
+	n = curfile->lineno;
+	if (szstack[0] != 0)
+		printf(".nr %d \\n(.s\n", sz1 = salloc());
+	ds = salloc();
+	printf(".rm %d \n", ds);
+	display = 0;
+	do {
+		if (*in)
+			printf(".as %d \"%s\n", ds, in);
+		init();
+		yyparse();
+		if (eqnreg > 0) {
+			printf(".as %d \\*(%d\n", ds, eqnreg);
+			sfree(eqnreg);
+			printf(".lf %d\n", curfile->lineno+1);
+		}
+	} while (getline(in) == lefteq);
+	if (*in)
+		printf(".as %d \"%s", ds, in);
+	if (sz1)
+		printf("\\s\\n(%d", sz1);
+	printf("\\*(%d\n", ds);
+	printf(".lf %d\n", curfile->lineno+1);
+	if (curfile->lineno > n+3)
+		fprintf(stderr, "eqn warning: multi-line %c...%c, file %s:%d,%d\n",
+			lefteq, righteq, curfile->fname, n, curfile->lineno); 
+	sfree(ds);
+	if (sz1) sfree(sz1);
+}
+
+void putout(int p1)
+{
+	double before, after;
+	extern double BeforeSub, AfterSub;
+
+	dprintf(".\tanswer <- S%d, h=%g,b=%g\n",p1, eht[p1], ebase[p1]);
+	eqnht = eht[p1];
+	before = eht[p1] - ebase[p1] - BeforeSub;	/* leave room for sub or superscript */
+	after = ebase[p1] - AfterSub;
+	if (spaceval || before > 0.01 || after > 0.01) {
+		printf(".ds %d ", p1);	/* used to be \\x'0' here:  why? */
+		if (spaceval != NULL)
+			printf("\\x'0-%s'", spaceval);
+		else if (before > 0.01)
+			printf("\\x'0-%gm'", before);
+		printf("\\*(%d", p1);
+		if (spaceval == NULL && after > 0.01)
+			printf("\\x'%gm'", after);
+		putchar('\n');
+	}
+	if (szstack[0] != 0)
+		printf(".ds %d %s\\*(%d\\s\\n(99\n", p1, DPS(gsize,gsize), p1);
+	eqnreg = p1;
+	if (spaceval != NULL) {
+		free(spaceval);
+		spaceval = NULL;
+	}
+}
+
+void init(void)
+{
+	synerr = 0;
+	ct = 0;
+	ps = gsize;
+	ftp = ftstack;
+	ft = ftp->ft;
+	nszstack = 0;
+	if (szstack[0] != 0)	/* absolute gsize in effect */
+		printf(".nr 99 \\n(.s\n");
+}
+
+salloc(void)
+{
+	int i;
+
+	for (i = 11; i < 100; i++)
+		if (used[i] == 0) {
+			used[i]++;
+			return(i);
+		}
+	ERROR "no eqn strings left (%d)", i FATAL;
+	return(0);
+}
+
+void sfree(int n)
+{
+	used[n] = 0;
+}
+
+void nrwid(int n1, int p, int n2)
+{
+	printf(".nr %d 0\\w'%s\\*(%d'\n", n1, DPS(gsize,p), n2);	/* 0 defends against - width */
+}
+
+char *ABSPS(int dn)	/* absolute size dn in printable form \sd or \s(dd (dd >= 40) */
+{
+	static char buf[100], *lb = buf;
+	char *p;
+
+	if (lb > buf + sizeof(buf) - 10)
+		lb = buf;
+	p = lb;
+	*lb++ = '\\';
+	*lb++ = 's';
+	if (dn >= 10) {		/* \s(dd only works in new troff */
+		if (dn >= 40)
+			*lb++ = '(';
+		*lb++ = dn/10 + '0';
+		*lb++ = dn%10 + '0';
+	} else {
+		*lb++ = dn + '0';
+	}
+	*lb++ = '\0';	
+	return p;
+}
+
+char *DPS(int f, int t)	/* delta ps (t-f) in printable form \s+d or \s-d or \s+-(dd */
+{
+	static char buf[100], *lb = buf;
+	char *p;
+	int dn;
+
+	if (lb > buf + sizeof(buf) - 10)
+		lb = buf;
+	p = lb;
+	*lb++ = '\\';
+	*lb++ = 's';
+	dn = EFFPS(t) - EFFPS(f);
+	if (szstack[nszstack] != 0)	/* absolute */
+		dn = EFFPS(t);		/* should do proper \s(dd */
+	else if (dn >= 0)
+		*lb++ = '+';
+	else {
+		*lb++ = '-';
+		dn = -dn;
+	}
+	if (dn >= 10) {		/* \s+(dd only works in new troff */
+		*lb++ = '(';
+		*lb++ = dn/10 + '0';
+		*lb++ = dn%10 + '0';
+	} else {
+		*lb++ = dn + '0';
+	}
+	*lb++ = '\0';	
+	return p;
+}
+
+EFFPS(int n)	/* effective value of n */
+{
+	if (n >= minsize)
+		return n;
+	else
+		return minsize;
+}
+
+double EM(double m, int ps)	/* convert m to ems in gsize */
+{
+	m *= (double) EFFPS(ps) / gsize;
+	if (m <= 0.001 && m >= -0.001)
+		return 0;
+	else
+		return m;
+}
+
+double REL(double m, int ps)	/* convert m to ems in ps */
+{
+	m *= (double) gsize / EFFPS(ps);
+	if (m <= 0.001 && m >= -0.001)
+		return 0;
+	else
+		return m;
+}
diff --git a/src/cmd/eqn/mark.c b/src/cmd/eqn/mark.c
new file mode 100644
index 00000000..f02e6779
--- /dev/null
+++ b/src/cmd/eqn/mark.c
@@ -0,0 +1,19 @@
+#include "e.h"
+
+void mark(int p1)
+{
+	markline = 1;
+	printf(".ds %d \\k(09\\*(%d\n", p1, p1);
+	yyval = p1;
+	dprintf(".\tmark %d\n", p1);
+}
+
+void lineup(int p1)
+{
+	markline = 2;
+	if (p1 == 0) {
+		yyval = salloc();
+		printf(".ds %d \\h'|\\n(09u'\n", yyval);
+	}
+	dprintf(".\tlineup %d\n", p1);
+}
diff --git a/src/cmd/eqn/matrix.c b/src/cmd/eqn/matrix.c
new file mode 100644
index 00000000..9df6cff2
--- /dev/null
+++ b/src/cmd/eqn/matrix.c
@@ -0,0 +1,78 @@
+#include "e.h"
+
+startcol(int type)	/* mark start of column in lp[] array */
+{
+	int oct = ct;
+
+	lp[ct++] = type;
+	lp[ct++] = 0;	/* count, to come */
+	lp[ct++] = 0;	/* separation, to come */
+	return oct;
+}
+
+void column(int oct, int sep)	/* remember end of column that started at lp[oct] */
+{
+	int i, type;
+
+	lp[oct+1] = ct - oct - 3;
+	lp[oct+2] = sep;
+	type = lp[oct];
+	if (dbg) {
+		printf(".\t%d column of", type);
+		for (i = oct+3; i < ct; i++ )
+			printf(" S%d", lp[i]);
+		printf(", rows=%d, sep=%d\n", lp[oct+1], lp[oct+2]);
+	}
+}
+
+void matrix(int oct)	/* matrix is list of columns */
+{
+	int nrow, ncol, i, j, k, val[100];
+	double b, hb;
+	char *space;
+	extern char *Matspace;
+
+	space = Matspace;	/* between columns of matrix */
+	nrow = lp[oct+1];	/* disaster if rows inconsistent */
+				/* also assumes just columns */
+				/* fix when add other things */
+	ncol = 0;
+	for (i = oct+1; i < ct; i += lp[i]+3 ) {
+		ncol++;
+		dprintf(".\tcolct=%d\n", lp[i]);
+	}
+	for (k=1; k <= nrow; k++) {
+		hb = b = 0;
+		j = oct + k + 2;
+		for (i=0; i < ncol; i++) {
+			hb = max(hb, eht[lp[j]]-ebase[lp[j]]);
+			b = max(b, ebase[lp[j]]);
+			j += nrow + 3;
+		}
+		dprintf(".\trow %d: b=%g, hb=%g\n", k, b, hb);
+		j = oct + k + 2;
+		for (i=0; i<ncol; i++) {
+			ebase[lp[j]] = b;
+			eht[lp[j]] = b + hb;
+			j += nrow + 3;
+		}
+	}
+	j = oct;
+	for (i=0; i<ncol; i++) {
+		pile(j);
+		val[i] = yyval;
+		j += nrow + 3;
+	}
+	yyval = salloc();
+	eht[yyval] = eht[val[0]];
+	ebase[yyval] = ebase[val[0]];
+	lfont[yyval] = rfont[yyval] = 0;
+	dprintf(".\tmatrix S%d: r=%d, c=%d, h=%g, b=%g\n",
+		yyval,nrow,ncol,eht[yyval],ebase[yyval]);
+	printf(".ds %d \"", yyval);
+	for( i=0; i<ncol; i++ )  {
+		printf("\\*(%d%s", val[i], i==ncol-1 ? "" : space);
+		sfree(val[i]);
+	}
+	printf("\n");
+}
diff --git a/src/cmd/eqn/mkfile b/src/cmd/eqn/mkfile
new file mode 100644
index 00000000..5f8e559c
--- /dev/null
+++ b/src/cmd/eqn/mkfile
@@ -0,0 +1,42 @@
+<$PLAN9/src/mkhdr
+
+TARG=eqn
+OFILES=main.$O\
+	tuning.$O\
+	diacrit.$O\
+	eqnbox.$O\
+	font.$O\
+	fromto.$O\
+	funny.$O\
+	glob.$O\
+	integral.$O\
+	input.$O\
+	lex.$O\
+	lookup.$O\
+	mark.$O\
+	matrix.$O\
+	move.$O\
+	over.$O\
+	paren.$O\
+	pile.$O\
+	shift.$O\
+	size.$O\
+	sqrt.$O\
+	text.$O\
+	eqn.$O\
+
+YFILES=eqn.y\
+
+HFILES=e.h\
+	y.tab.h\
+
+SHORTLIB=bio 9
+<$PLAN9/src/mkone
+
+YFLAGS=-d -S
+
+eqn.c:	y.tab.c prevy.tab.h
+	mv y.tab.c $target
+
+prevy.tab.h:	y.tab.h
+	sh -c 'cmp -s y.tab.h prevy.tab.h || cp y.tab.h prevy.tab.h'
diff --git a/src/cmd/eqn/move.c b/src/cmd/eqn/move.c
new file mode 100644
index 00000000..a622487c
--- /dev/null
+++ b/src/cmd/eqn/move.c
@@ -0,0 +1,19 @@
+# include "e.h"
+# include "y.tab.h"
+
+void move(int dir, int amt, int p)
+{
+	double a;
+
+	yyval = p;
+	a = EM(amt/100.0, ps);
+	printf(".ds %d ", yyval);
+	if (dir == FWD || dir == BACK)
+		printf("\\h'%s%gm'\\*(%d\n", (dir==BACK) ? "-" : "", a, p);
+	else if (dir == UP)
+		printf("\\v'-%gm'\\*(%d\\v'%gm'\n", a, p, a);
+	else if (dir == DOWN)
+		printf("\\v'%gm'\\*(%d\\v'-%gm'\n", a, p, a);
+	dprintf(".\tmove %d dir %d amt %g; h=%g b=%g\n", 
+		p, dir, a, eht[yyval], ebase[yyval]);
+}
diff --git a/src/cmd/eqn/o.eqn b/src/cmd/eqn/o.eqn
new file mode 100755
index 00000000..61f93ddf
--- /dev/null
+++ b/src/cmd/eqn/o.eqn
diff --git a/src/cmd/eqn/over.c b/src/cmd/eqn/over.c
new file mode 100644
index 00000000..2794a739
--- /dev/null
+++ b/src/cmd/eqn/over.c
@@ -0,0 +1,35 @@
+#include "e.h"
+
+void boverb(int p1, int p2)
+{
+	int treg;
+	double h, b, d, d1, d2;
+	extern double Overgap, Overwid, Overline;
+
+	treg = salloc();
+	yyval = p1;
+	d = EM(Overgap, ps);
+	h = eht[p1] + eht[p2] + d;
+	b = eht[p2] - d;
+	dprintf(".\tS%d <- %d over %d; b=%g, h=%g\n", 
+		yyval, p1, p2, b, h);
+	nrwid(p1, ps, p1);
+	nrwid(p2, ps, p2);
+	printf(".nr %d \\n(%d\n", treg, p1);
+	printf(".if \\n(%d>\\n(%d .nr %d \\n(%d\n", p2, treg, treg, p2);
+	printf(".nr %d \\n(%d+%gm\n", treg, treg, Overwid);
+	d2 = eht[p2]-ebase[p2]-d;	/* denom */
+	printf(".ds %d \\v'%gm'\\h'\\n(%du-\\n(%du/2u'\\*(%d\\v'%gm'\\\n", 
+		yyval, REL(d2,ps), treg, p2, p2, REL(-d2,ps));
+	d1 = 2 * d + ebase[p1];		/* num */
+	printf("\\h'-\\n(%du-\\n(%du/2u'\\v'%gm'\\*(%d\\v'%gm'\\\n", 
+		p2, p1, REL(-d1,ps), p1, REL(d1,ps));
+	printf("\\h'-\\n(%du-\\n(%du/2u+%gm'\\v'%gm'\\l'\\n(%du-%gm'\\h'%gm'\\v'%gm'\n", 
+		treg, p1, Overline, REL(-d,ps),
+		treg, 2*Overline, Overline, REL(d,ps));
+	ebase[yyval] = b;
+	eht[yyval] = h;
+	lfont[yyval] = rfont[yyval] = 0;
+	sfree(p2);
+	sfree(treg);
+}
diff --git a/src/cmd/eqn/paren.c b/src/cmd/eqn/paren.c
new file mode 100644
index 00000000..bb019bf7
--- /dev/null
+++ b/src/cmd/eqn/paren.c
@@ -0,0 +1,135 @@
+#include "e.h"
+
+#define abs(x) ((x) > 0 ? (x) : (-(x)))
+
+extern void brack(int, char *, char *, char *);
+
+void paren(int leftc, int p1, int rightc)
+{
+	int n, m, j;
+	double h1, b1;
+	double v, bv;	/* v = shift of inside, bv = shift of brackets */
+	extern double Parenbase, Parenshift, Parenheight;
+
+	bv = ttype == DEVPOST ? Parenshift : 0;	/* move brackets down this much */
+	h1 = eht[p1];
+	b1 = ebase[p1];
+	yyval = p1;
+	lfont[yyval] = rfont[yyval] = 0;
+	n = REL(h1,ps) + 0.99;	/* ceiling */
+	if (n < 2)
+		n = 1;
+	m = n - 2;
+	if (leftc == '{' || rightc == '}') {
+		n = n%2 ? n : ++n;
+		if (n < 3)
+			n = 3;
+		m = n-3;
+	}
+	eht[yyval] = EM((double) n + Parenheight, ps);
+	ebase[yyval] = eht[yyval]/2 - EM(Parenbase, ps);
+
+	/* try to cope with things that are badly centered */
+	/* (top heavy or bottom heavy) */
+	if (abs(h1/2 - b1) >= EM(0.5, ps))
+		v = REL(-ebase[yyval] + (eht[yyval]-h1)/2 + b1, ps);
+	else
+		v = 0;	/* don't shift it at all */
+
+	printf(".ds %d \\^", yyval);	/* was \| */
+	if (bv)
+		printf("\\v'%gm'", bv);
+	switch (leftc) {
+	case 'n':	/* nothing */
+	case '\0':
+		break;
+	case 'f':	/* floor */
+		if (n <= 1)
+			printf("\\(lf");
+		else
+			brack(m, "\\(bv", "\\(bv", "\\(lf");
+		break;
+	case 'c':	/* ceiling */
+		if (n <= 1)
+			printf("\\(lc");
+		else
+			brack(m, "\\(lc", "\\(bv", "\\(bv");
+		break;
+	case '{':
+		printf("\\b'\\(lt");
+		for(j = 0; j < m; j += 2) printf("\\(bv");
+		printf("\\(lk");
+		for(j = 0; j < m; j += 2) printf("\\(bv");
+		printf("\\(lb'");
+		break;
+	case '(':
+		brack(m, "\\(lt", "\\(bv", "\\(lb");
+		break;
+	case '[':
+		brack(m, "\\(lc", "\\(bv", "\\(lf");
+		break;
+	case '|':
+		brack(m, "|", "|", "|");
+		break;
+	default:
+		brack(m, (char *) &leftc, (char *) &leftc, (char *) &leftc);
+		break;
+	}
+	if (bv)
+		printf("\\v'%gm'", -bv);
+	if (v)
+		printf("\\v'%gm'\\*(%d\\v'%gm'", -v, p1, v);
+	else
+		printf("\\*(%d", p1);
+	if (rightc) {
+		if (bv)
+			printf("\\v'%gm'", bv);
+		switch (rightc) {
+		case 'f':	/* floor */
+			if (n <= 1)
+				printf("\\(rf");
+			else
+				brack(m, "\\(bv", "\\(bv", "\\(rf");
+			break;
+		case 'c':	/* ceiling */
+			if (n <= 1)
+				printf("\\(rc");
+			else
+				brack(m, "\\(rc", "\\(bv", "\\(bv");
+			break;
+		case '}':
+			printf("\\b'\\(rt");
+			for(j = 0; j < m; j += 2) printf("\\(bv");
+			printf("\\(rk");
+			for(j = 0; j < m; j += 2) printf("\\(bv");
+			printf("\\(rb'");
+			break;
+		case ']':
+			brack(m, "\\(rc", "\\(bv", "\\(rf");
+			break;
+		case ')':
+			brack(m, "\\(rt", "\\(bv", "\\(rb");
+			break;
+		case '|':
+			brack(m, "|", "|", "|");
+			break;
+		default:
+			brack(m, (char *) &rightc, (char *) &rightc, (char *) &rightc);
+			break;
+		}
+		if (bv)
+			printf("\\v'%gm'", -bv);
+	}
+	printf("\n");
+	dprintf(".\tcurly: h=%g b=%g n=%d v=%g l=%c, r=%c\n", 
+		eht[yyval], ebase[yyval], n, v, leftc, rightc);
+}
+
+void brack(int m, char *t, char *c, char *b)
+{
+	int j;
+	printf("\\b'%s", t);
+	for( j=0; j < m; j++)
+		printf("%s", c);
+	printf("%s'", b);
+}
diff --git a/src/cmd/eqn/pile.c b/src/cmd/eqn/pile.c
new file mode 100644
index 00000000..a2d16239
--- /dev/null
+++ b/src/cmd/eqn/pile.c
@@ -0,0 +1,76 @@
+#include "e.h"
+#include "y.tab.h"
+
+void pile(int oct)
+{
+	int i, nlist, nlist2, mid;
+	double bi, h, b, gap, sb;
+	extern double Pilegap, Pilebase;
+	int type, p1, p2;
+
+	yyval = salloc();
+	type = lp[oct];
+	p1 = oct + 3;		/* first entry */
+	p2 = p1 + lp[oct+1];	/* 1 after last */
+	gap = lp[oct+2];
+	if (gap != DEFGAP)
+		gap = EM(gap/100.0, ps);
+	else if (type == COL)
+		gap = 0;
+	else
+		gap = EM(Pilegap, ps);	/* 0.4 m between LCOL, etc. */
+	nlist = p2 - p1;
+	nlist2 = (nlist+1)/2;
+	mid = p1 + nlist2 - 1;
+	h = 0;
+	for (i = p1; i < p2; i++)
+		h += eht[lp[i]];
+	eht[yyval] = h + (nlist-1)*gap;
+	b = 0;
+	for (i = p2-1; i > mid; i--)
+		b += eht[lp[i]] + gap;
+	ebase[yyval] = (nlist%2) ? b + ebase[lp[mid]]
+			: b - EM(Pilebase, ps) - gap;
+	if (dbg) {
+		printf(".\tS%d <- %d pile of:", yyval, type);
+		for (i = p1; i < p2; i++)
+			printf(" S%d", lp[i]);
+		printf("; h=%g b=%g\n", eht[yyval], ebase[yyval]);
+	}
+	nrwid(lp[p1], ps, lp[p1]);
+	printf(".nr %d \\n(%d\n", yyval, lp[p1]);
+	for (i = p1+1; i < p2; i++) {
+		nrwid(lp[i], ps, lp[i]);
+		printf(".if \\n(%d>\\n(%d .nr %d \\n(%d\n", 
+			lp[i], yyval, yyval, lp[i]);
+	}
+	printf(".ds %d \\v'%gm'\\h'%du*\\n(%du'\\\n", yyval, REL(ebase[yyval],ps), 
+		type==RCOL ? 1 : 0, yyval);
+	sb = 0;		/* sum of box hts */
+	for (i = p2-1; i >= p1; i--) {
+		bi = sb + ebase[lp[i]];
+		switch (type) {
+		case LCOL:
+			printf("\\v'%gm'\\*(%d\\h'-\\n(%du'\\v'%gm'\\\n", 
+				REL(-bi,ps), lp[i], lp[i], REL(bi,ps));
+			break;
+		case RCOL:
+			printf("\\v'%gm'\\h'-\\n(%du'\\*(%d\\v'%gm'\\\n", 
+				REL(-bi,ps), lp[i], lp[i], REL(bi,ps));
+			break;
+		case CCOL:
+		case COL:
+			printf("\\v'%gm'\\h'\\n(%du-\\n(%du/2u'\\*(%d", 
+				REL(-bi,ps), yyval, lp[i], lp[i]);
+			printf("\\h'-\\n(%du-\\n(%du/2u'\\v'%gm'\\\n", 
+				yyval, lp[i], REL(bi,ps));
+			break;
+		}
+		sb += eht[lp[i]] + gap;
+	}
+	printf("\\v'%gm'\\h'%du*\\n(%du'\n", REL(-ebase[yyval],ps), 
+		type!=RCOL ? 1 : 0, yyval);
+	for (i = p1; i < p2; i++)
+		sfree(lp[i]);
+	lfont[yyval] = rfont[yyval] = 0;
+}
diff --git a/src/cmd/eqn/prevy.tab.h b/src/cmd/eqn/prevy.tab.h
new file mode 100644
index 00000000..1f6d3c71
--- /dev/null
+++ b/src/cmd/eqn/prevy.tab.h
@@ -0,0 +1,57 @@
+#define	CONTIG	57346
+#define	QTEXT	57347
+#define	SPACE	57348
+#define	THIN	57349
+#define	TAB	57350
+#define	MATRIX	57351
+#define	LCOL	57352
+#define	CCOL	57353
+#define	RCOL	57354
+#define	COL	57355
+#define	ABOVE	57356
+#define	MARK	57357
+#define	LINEUP	57358
+#define	SUM	57359
+#define	INT	57360
+#define	PROD	57361
+#define	UNION	57362
+#define	INTER	57363
+#define	DEFINE	57364
+#define	TDEFINE	57365
+#define	NDEFINE	57366
+#define	DELIM	57367
+#define	GSIZE	57368
+#define	GFONT	57369
+#define	INCLUDE	57370
+#define	IFDEF	57371
+#define	DOTEQ	57372
+#define	DOTEN	57373
+#define	FROM	57374
+#define	TO	57375
+#define	OVER	57376
+#define	SQRT	57377
+#define	SUP	57378
+#define	SUB	57379
+#define	SIZE	57380
+#define	FONT	57381
+#define	ROMAN	57382
+#define	ITALIC	57383
+#define	BOLD	57384
+#define	FAT	57385
+#define	UP	57386
+#define	DOWN	57387
+#define	BACK	57388
+#define	FWD	57389
+#define	LEFT	57390
+#define	RIGHT	57391
+#define	DOT	57392
+#define	DOTDOT	57393
+#define	HAT	57394
+#define	TILDE	57395
+#define	BAR	57396
+#define	LOWBAR	57397
+#define	HIGHBAR	57398
+#define	UNDER	57399
+#define	VEC	57400
+#define	DYAD	57401
+#define	UTILDE	57402
diff --git a/src/cmd/eqn/shift.c b/src/cmd/eqn/shift.c
new file mode 100644
index 00000000..dbac530b
--- /dev/null
+++ b/src/cmd/eqn/shift.c
@@ -0,0 +1,116 @@
+#include "e.h"
+#include "y.tab.h"
+
+void subsup(int p1, int p2, int p3)
+{
+	if (p2 != 0 && p3 != 0)
+		shift2(p1, p2, p3);
+	else if (p2 != 0)
+		bshiftb(p1, SUB, p2);
+	else if (p3 != 0)
+		bshiftb(p1, SUP, p3);
+}
+
+extern double Subbase, Supshift;
+extern char *Sub1space, *Sup1space, *Sub2space;
+extern char *SS1space, *SS2space;
+
+void bshiftb(int p1, int dir, int p2)
+{
+	int subps, n;
+	double shval, d1, h1, b1, h2, b2;
+	char *sh1, *sh2;
+
+	yyval = p1;
+	h1 = eht[p1];
+	b1 = ebase[p1];
+	h2 = eht[p2];
+	b2 = ebase[p2];
+	subps = ps;
+	ps += deltaps;
+	if (dir == SUB) {
+		/* base .2m below bottom of main box */
+		shval = b1 + EM(Subbase, ps);
+		ebase[yyval] = shval + b2;
+		eht[yyval] = max(h1-b1+shval+b2, h2);
+		if (rfont[p1] == ITAL && lfont[p2] == ROM)
+			n = 2;		/* Sub1space */
+		else
+			n = max(2, class[rclass[p1]][lclass[p2]]);
+		sh1 = pad(n);
+		rclass[p1] = OTHER;	/* OTHER leaves too much after sup */
+	} else {	/* superscript */
+		/* 4/10 up main box */
+		d1 = EM(Subbase, subps);
+		ebase[yyval] = b1;
+		shval = -(Supshift * (h1-b1)) - b2;
+		if (Supshift*(h1-b1) + h2 < h1-b1)	/* raise little super */
+			shval = -(h1-b1) + h2-b2 - d1;
+		eht[yyval] = h1 + max(0, h2 - (1-Supshift)*(h1-b1));
+		if (rclass[p1] == ILETF)
+			n = 4;
+		else if (rfont[p1] == ITAL)
+			n = 2;		/* Sup1space */
+		else
+			n = max(1, class[rclass[p1]][lclass[p2]]);
+		sh1 = pad(n);
+		rclass[p1] = rclass[p2];	/* OTHER leaves too much after sup */
+	}
+	dprintf(".\tS%d <- %d shift %g %d; b=%g, h=%g, ps=%d, subps=%d\n", 
+		yyval, p1, shval, p2, ebase[yyval], eht[yyval], ps, subps);
+	sh2 = Sub2space;	/* was Sub2space; */
+	printf(".as %d \\v'%gm'%s%s\\*(%d%s%s\\v'%gm'\n", 
+		yyval, REL(shval,ps), DPS(ps,subps), sh1, p2,
+		DPS(subps,ps), sh2, REL(-shval,ps));
+	rfont[p1] = 0;
+	sfree(p2);
+}
+
+void shift2(int p1, int p2, int p3)
+{
+	int subps;
+	double h1, h2, h3, b1, b2, b3, subsh, d2, supsh;
+	int treg;
+	char *sh2;
+
+	treg = salloc();
+	yyval = p1;
+	subps = ps;	/* sub and sup at this size */
+	ps += deltaps;	/* outer size */
+	h1 = eht[p1]; b1 = ebase[p1];
+	h2 = eht[p2]; b2 = ebase[p2];
+	h3 = eht[p3]; b3 = ebase[p3];
+	subsh = EM(Subbase, ps);
+	if (b1 > b2 + subsh) /* move little sub down */
+		subsh += b1;
+	eht[yyval] = max(subsh+b2-b1+h1, h2);
+	supsh = -Supshift*(h1-b1) - b3;
+	d2 = EM(Subbase, subps);
+	if (h3 < (1-Supshift)*(h1-b1))
+		supsh = -(h1-b1) + (h3-b3) - d2;
+	ebase[yyval] = subsh + b2 - b1;
+	eht[yyval] = h1 + subsh+b2-b1 + max(0, h3-(1-Supshift)*(h1-b1));
+	dprintf(".\tS%d <- %d sub %d sup %d, ps=%d, subps=%d, h=%g, b=%g\n",
+		yyval, p1, p2, p3, ps, subps, eht[yyval], ebase[yyval]);
+	if (rclass[p1] == ILETF)
+		sh2 = "\\|\\|";
+	else
+		sh2 = SS2space;
+	/*n = max(class[rclass[p1]][lclass[p2]], class[rclass[p1]][lclass[p3]]);
+	/*sh2 = pad(max(2, n));
+	*/
+	printf(".ds %d %s\\*(%d\n", p2, SS1space, p2);
+	nrwid(p2, subps, p2);
+	printf(".ds %d %s\\*(%d\n", p3, sh2, p3);
+	nrwid(p3, subps, p3);
+	printf(".nr %d \\n(%d\n", treg, p3);
+	printf(".if \\n(%d>\\n(%d .nr %d \\n(%d\n", p2, treg, treg, p2);
+	printf(".as %d %s\\v'%gm'\\*(%d\\v'%gm'\\h'-\\n(%du'\\\n", 
+		p1, DPS(ps,subps), REL(subsh,subps), p2, REL(-subsh,subps), p2);
+	printf("\\v'%gm'\\*(%d\\v'%gm'\\h'-\\n(%du+\\n(%du'%s%s\n", 
+		REL(supsh,subps), p3, REL(-supsh,subps), p3, treg, DPS(subps,ps), Sub2space);
+	if (rfont[p2] == ITAL)
+		rfont[yyval] = 0;	/* lie */
+	rclass[yyval] = rclass[p3];	/* was OTHER */
+	sfree(p2); sfree(p3); sfree(treg);
+}
diff --git a/src/cmd/eqn/size.c b/src/cmd/eqn/size.c
new file mode 100644
index 00000000..59bf3f20
--- /dev/null
+++ b/src/cmd/eqn/size.c
@@ -0,0 +1,70 @@
+#include "e.h"
+#include <ctype.h>
+
+void setsize(char *p)	/* set size as found in p */
+{
+	nszstack++;
+	szstack[nszstack] = 0;		/* assume relative */
+	if (*p == '+') {
+		ps += atoi(p+1);
+		if (szstack[nszstack-1] != 0)	/* propagate absolute size */
+			szstack[nszstack] = ps;
+	} else if (*p == '-') {
+		ps -= atoi(p+1);
+		if (szstack[nszstack-1] != 0)
+			szstack[nszstack] = ps;
+	} else if (isdigit(*p)) {
+		if (szstack[nszstack-1] == 0)
+			printf(".nr %d \\n(.s\n", 99-nszstack);
+		else
+			printf(".nr %d %d\n", 99-nszstack, ps);
+		szstack[nszstack] = ps = atoi(p);
+	} else {
+		ERROR "illegal size %s ignored", p WARNING;
+	}
+	dprintf(".\tsetsize %s; ps = %d\n", p, ps);
+}
+
+void size(int p1, int p2)
+{
+		/* old size in p1, new in ps */
+	yyval = p2;
+	dprintf(".\tS%d <- \\s%d %d \\s%d; b=%g, h=%g\n", 
+		yyval, ps, p2, p1, ebase[yyval], eht[yyval]);
+	if (szstack[nszstack] != 0) {
+		printf(".ds %d %s\\*(%d\\s\\n(%d\n", yyval, ABSPS(ps), p2, 99-nszstack);
+	} else
+		printf(".ds %d %s\\*(%d%s\n", yyval, DPS(p1,ps), p2, DPS(ps,p1));
+	nszstack--;
+	ps = p1;
+}
+
+void globsize(void)
+{
+	char temp[20];
+
+	getstr(temp, sizeof(temp));
+	if (temp[0] == '+') {
+		gsize += atoi(temp+1);
+		if (szstack[0] != 0)
+			szstack[0] = gsize;
+	} else if (temp[0] == '-') {
+		gsize -= atoi(temp+1);
+		if (szstack[0] != 0)
+			szstack[0] = gsize;
+	} else  if (isdigit(temp[0])) {
+		gsize = atoi(temp);
+		szstack[0] = gsize;
+		printf(".nr 99 \\n(.s\n");
+	} else {
+		ERROR "illegal gsize %s ignored", temp WARNING;
+	}
+	yyval = eqnreg = 0;
+	ps = gsize;
+	if (gsize < 12 && !dps_set)		/* sub and sup size change */
+		deltaps = gsize / 3;
+	else if (gsize < 20)
+		deltaps = gsize / 4;
+	else
+		deltaps = gsize / 5;
+}
diff --git a/src/cmd/eqn/sqrt.c b/src/cmd/eqn/sqrt.c
new file mode 100644
index 00000000..391d924e
--- /dev/null
+++ b/src/cmd/eqn/sqrt.c
@@ -0,0 +1,35 @@
+#include "e.h"
+
+void sqrt(int p2)
+{
+	static int af = 0;
+	int nps;	/* point size for radical */
+	double radscale = 0.95;
+
+	if (ttype == DEVPOST)
+		radscale = 1.05;
+	nps = ps * radscale * eht[p2] / EM(1.0,ps) + 0.99;	/* kludgy */
+	nps = max(EFFPS(nps), ps);
+	yyval = p2;
+	if (ttype == DEVCAT || ttype == DEVAPS)
+		eht[yyval] = EM(1.2, nps);
+	else if (ttype == DEVPOST)
+		eht[yyval] = EM(1.15, nps);
+	else		/* DEV202, DEVPOST */
+		eht[yyval] = EM(1.15, nps);
+	dprintf(".\tS%d <- sqrt S%d;b=%g, h=%g, nps=%d\n", 
+		yyval, p2, ebase[yyval], eht[yyval], nps);
+	printf(".as %d \\|\n", yyval);
+	nrwid(p2, ps, p2);
+	if (af++ == 0)
+		printf(".af 10 01\n");	/* make it two digits when it prints */
+	printf(".nr 10 %.3fu*\\n(.su/10\n", 9.2*eht[p2]);	/* this nonsense */
+			/* guesses point size corresponding to height of stuff */
+	printf(".ds %d \\v'%gm'\\s(\\n(10", yyval, REL(ebase[p2],ps));
+	if (ttype == DEVCAT || ttype == DEVAPS)
+		printf("\\v'-.2m'\\(sr\\l'\\n(%du\\(rn'\\v'.2m'", p2);
+	else		/* DEV202, DEVPOST so far */
+		printf("\\(sr\\l'\\n(%du\\(rn'", p2);
+	printf("\\s0\\v'%gm'\\h'-\\n(%du'\\^\\*(%d\n", REL(-ebase[p2],ps), p2, p2);
+	lfont[yyval] = rfont[yyval] = ROM;
+}
diff --git a/src/cmd/eqn/text.c b/src/cmd/eqn/text.c
new file mode 100644
index 00000000..261c7fbf
--- /dev/null
+++ b/src/cmd/eqn/text.c
@@ -0,0 +1,318 @@
+#include "e.h"
+#include "y.tab.h"
+#include <ctype.h>
+
+#define	CSSIZE	1000
+char	cs[CSSIZE+20];	/* text string converted into this */
+char	*csp;		/* next spot in cs[] */
+char	*psp;		/* next character in input token */
+
+int	lf, rf;		/* temporary spots for left and right fonts */
+int	lastft;		/* last \f added */
+int	nextft;		/* next \f to be added */
+
+int	pclass;		/* class of previous character */
+int	nclass;		/* class of next character */
+
+int class[LAST][LAST] ={	/* guesswork, tuned to times roman postscript */
+
+	/*OT OL IL DG LP RP SL PL IF IJ VB */
+/*OT*/	{ 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 0 },		/* OTHER */
+/*OL*/	{ 1, 0, 1, 1, 1, 1, 1, 2, 2, 2, 0 },		/* OLET */
+/*IL*/	{ 1, 1, 0, 1, 1, 1, 1, 3, 2, 1, 0 },		/* ILET */
+/*DG*/	{ 1, 1, 1, 0, 1, 1, 1, 2, 2, 2, 0 },		/* DIG */
+/*LP*/	{ 1, 1, 1, 1, 1, 2, 1, 2, 3, 3, 0 },		/* LPAR */
+/*RP*/	{ 2, 2, 2, 1, 1, 1, 1, 2, 3, 3, 0 },		/* RPAR */
+/*SL*/	{ 1, 1, 1, 1, 1, 1, 1, 2, 2, 1, 0 },		/* SLASH */
+/*PL*/	{ 2, 2, 2, 2, 2, 2, 3, 2, 3, 2, 0 },		/* PLUS */
+/*IF*/	{ 3, 3, 1, 2, 2, 3, 2, 3, 0, 1, 1 },		/* ILETF */
+/*IJ*/	{ 1, 1, 1, 1, 1, 1, 1, 2, 2, 0, 0 },		/* ILETJ */
+/*VB*/	{ 4, 4, 4, 4, 4, 4, 4, 4, 5, 4, 1 },		/* VBAR */
+
+};
+
+extern void shim(int, int);
+extern void roman(int);
+extern void sadd(char *);
+extern void cadd(int);
+extern int trans(int, char *);
+
+int textc(void)	/* read next UTF rune from psp */
+{
+	wchar_t r;
+	int w;
+
+	w = mbtowc(&r, psp, 3);
+	if(w == 0){
+		psp++;
+		return 0;
+	}
+	if(w < 0){
+		psp += 1;
+		return 0x80;	/* Plan 9-ism */
+	}
+	psp += w;
+	return r;
+}
+
+void text(int t, char *p1)	/* convert text string p1 of type t */
+{
+	int c;
+	char *p;
+	tbl *tp;
+
+	yyval = salloc();
+	ebase[yyval] = 0;
+	eht[yyval] = EM(1.0, ps);	/* ht in ems of orig size */
+	lfont[yyval] = rfont[yyval] = ROM;
+	lclass[yyval] = rclass[yyval] = OTHER;
+	if (t == QTEXT) {
+		for (p = p1; *p; p++)	/* scan for embedded \f's */
+			if (*p == '\\' && *(p+1) == 'f')
+				break;
+		if (*p)		/* if found \f, leave it alone and hope */
+			p = p1;
+		else {
+			sprintf(cs, "\\f%s%s\\fP", ftp->name, p1);
+			p = cs;
+		}
+	} else if (t == SPACE)
+		p = "\\ ";
+	else if (t == THIN)
+		p = "\\|";
+	else if (t == TAB)
+		p = "\\t";
+	else if ((tp = lookup(restbl, p1)) != NULL) {
+		p = tp->cval;
+	} else {
+		lf = rf = 0;
+		lastft = 0;
+		nclass = NONE;	/* get started with no class == no pad */
+		csp = cs;
+		for (psp = p1; (c = textc()) != '\0'; ) {
+			nextft = ft;
+			pclass = nclass;
+			rf = trans(c, p1);
+			if (lf == 0) {
+				lf = rf;	/* left stuff is first found */
+				lclass[yyval] = nclass;
+			}
+			if (csp-cs > CSSIZE)
+				ERROR "converted token %.25s... too long", p1 FATAL ;
+		}
+		sadd("\\fP");
+		*csp = '\0';
+		p = cs;
+		lfont[yyval] = lf;
+		rfont[yyval] = rf;
+		rclass[yyval] = nclass;
+	}
+	dprintf(".\t%dtext: S%d <- %s; b=%g,h=%g,lf=%c,rf=%c,ps=%d\n",
+		t, yyval, p, ebase[yyval], eht[yyval], lfont[yyval], rfont[yyval], ps);
+	printf(".ds %d \"%s\n", yyval, p);
+}
+
+int isalpharune(int c)
+{
+	return ('a'<=c && c<='z') || ('A'<=c && c<='Z');
+}
+
+int isdigitrune(int c)
+{
+	return ('0'<=c && c<='9');
+}
+
+trans(int c, char *p1)
+{
+	int f;
+
+	if (isalpharune(c) && ft == ITAL && c != 'f' && c != 'j') {	/* italic letter */
+		shim(pclass, nclass = ILET);
+		cadd(c);
+		return ITAL;
+	}
+	if (isalpharune(c) && ft != ITAL) {		/* other letter */
+		shim(pclass, nclass = OLET);
+		cadd(c);
+		return ROM;
+	}
+	if (isdigitrune(c)) {
+		shim(pclass, nclass = DIG);
+		roman(c);
+		return ROM;	/* this is the right side font of this object */
+	}
+	f = ROM;
+	nclass = OTHER;
+	switch (c) {
+	case ':': case ';': case '!': case '%': case '?':
+		shim(pclass, nclass);
+		roman(c);
+		return f;
+	case '(': case '[':
+		shim(pclass, nclass = LPAR);
+		roman(c);
+		return f;
+	case ')': case ']':
+		shim(pclass, nclass = RPAR);
+		roman(c);
+		return f;
+	case ',':
+		shim(pclass, nclass = OTHER);
+		roman(c);
+		return f;
+	case '.':
+		if (rf == ROM)
+			roman(c);
+		else
+			cadd(c);
+		return f;
+	case '|':		/* postscript needs help with default width! */
+		shim(pclass, nclass = VBAR);
+		sadd("\\v'.17m'\\z|\\v'-.17m'\\|");	/* and height */
+		return f;
+	case '=':
+		shim(pclass, nclass = PLUS);
+		sadd("\\(eq");
+		return f;
+	case '+':
+		shim(pclass, nclass = PLUS);
+		sadd("\\(pl");
+		return f;
+	case '>':
+	case '<':		/* >, >=, >>, <, <-, <=, << */
+		shim(pclass, nclass = PLUS);
+		if (*psp == '=') {
+			sadd(c == '<' ? "\\(<=" : "\\(>=");
+			psp++;
+		} else if (c == '<' && *psp == '-') {	/* <- only */
+			sadd("\\(<-");
+			psp++;
+		} else if (*psp == c) {		/* << or >> */
+			cadd(c);
+			cadd(c);
+			psp++;
+		} else {
+			cadd(c);  
+		}
+		return f;
+	case '-':
+		shim(pclass, nclass = PLUS);	/* probably too big for ->'s */
+		if (*psp == '>') {
+			sadd("\\(->");
+			psp++;
+		} else {
+			sadd("\\(mi");
+		}
+		return f;
+	case '/':
+		shim(pclass, nclass = SLASH);
+		cadd('/');
+		return f;
+	case '~':
+	case ' ':
+		sadd("\\|\\|");
+		return f;
+	case '^':
+		sadd("\\|");
+		return f;
+	case '\\':	/* troff - pass only \(xx without comment */
+		shim(pclass, nclass);
+		cadd('\\');
+		cadd(c = *psp++);
+		if (c == '(' && *psp && *(psp+1)) {
+			cadd(*psp++);
+			cadd(*psp++);
+		} else
+			fprintf(stderr, "eqn warning: unquoted troff command \\%c, file %s:%d\n",
+				c, curfile->fname, curfile->lineno);
+		return f;
+	case '\'':
+		shim(pclass, nclass);
+		sadd("\\(fm");
+		return f;
+
+	case 'f':
+		if (ft == ITAL) {
+			shim(pclass, nclass = ILETF);
+			cadd('f');
+			f = ITAL;
+		} else
+			cadd('f');
+		return f;
+	case 'j':
+		if (ft == ITAL) {
+			shim(pclass, nclass = ILETJ);
+			cadd('j');
+			f = ITAL;
+		} else
+			cadd('j');
+		return f;
+	default:
+		shim(pclass, nclass);
+		cadd(c);
+		return ft==ITAL ? ITAL : ROM;
+	}
+}
+
+char *pad(int n)	/* return the padding as a string */
+{
+	static char buf[20];
+
+	buf[0] = 0;
+	if (n < 0) {
+		sprintf(buf, "\\h'-%du*\\w'\\^'u'", -n);
+		return buf;
+	}	
+	for ( ; n > 1; n -= 2)
+		strcat(buf, "\\|");
+	if (n > 0)
+		strcat(buf, "\\^");
+	return buf;
+}
+
+void shim(int lc, int rc)	/* add padding space suitable to left and right classes */
+{
+	sadd(pad(class[lc][rc]));
+}
+
+void roman(int c)	/* add char c in "roman" font */
+{
+	nextft = ROM;
+	cadd(c);
+}
+
+void sadd(char *s)		/* add string s to cs */
+{
+	while (*s)
+		cadd(*s++);
+}
+
+void cadd(int c)		/* add character c to end of cs */
+{
+	char *p;
+	int w;
+
+	if (lastft != nextft) {
+		if (lastft != 0) {
+			*csp++ = '\\';
+			*csp++ = 'f';
+			*csp++ = 'P';
+		}
+		*csp++ = '\\';
+		*csp++ = 'f';
+		if (ftp == ftstack) {	/* bottom level */
+			if (ftp->ft == ITAL)	/* usual case */
+				*csp++ = nextft;
+			else		/* gfont set, use it */
+				for (p = ftp->name; *csp = *p++; )
+					csp++;
+		} else {	/* inside some kind of font ... */
+			for (p = ftp->name; *csp = *p++; )
+				csp++;
+		}
+		lastft = nextft;
+	}
+	w = wctomb(csp, c);
+	if(w > 0)	/* ignore bad characters */
+		csp += w;
+}
diff --git a/src/cmd/eqn/tuning.c b/src/cmd/eqn/tuning.c
new file mode 100644
index 00000000..99718db3
--- /dev/null
+++ b/src/cmd/eqn/tuning.c
@@ -0,0 +1,153 @@
+#include "e.h"
+
+/*
+
+This file contains parameter values for many of the
+tuning parameters in eqn.  Names are defined words.
+
+Strings are plugged in verbatim.
+Floats are usually in ems.
+
+*/
+
+/* In main.c: */
+
+double	BeforeSub = 1.2;	/* line space before a subscript */
+double	AfterSub  = 0.2;	/* line space after a subscript */
+
+/* diacrit.c: */
+
+double	Dvshift	= 0.25;		/* vertical shift for diacriticals on tall letters */
+double	Dhshift = 0.025;	/* horizontal shift for tall letters */
+double	Dh2shift = 0.05;	/* horizontal shift for small letters */
+double	Dheight	= 0.25;		/* increment to height for diacriticals */
+double	Barv	= 0.68;		/* vertical shift for bar */
+double	Barh	= 0.05;		/* 1/2 horizontal shrink for bar */
+double	Ubarv	= 0.1;		/* shift underbar up this much ems */
+double	Ubarh	= 0.05;		/* 1/2 horizontal shrink for underbar */
+
+/* Also:
+	Vec, Dyad, Hat, Tilde, Dot, Dotdot, Utilde */
+
+/* eqnbox.c: */
+
+char	*IRspace = "\\^";	/* space between italic & roman boxes */
+
+/* fat.c: */
+
+double	Fatshift = 0.05;	/* fattening shifts by Fatshift ems */
+
+/* funny.c: */
+
+int	Funnyps	= 5;		/* point size change (== 5 above) */
+double	Funnyht = 0.2;		/* height correction */
+double	Funnybase = 0.3;	/* base correction */
+
+/* integral.c: */
+
+int	Intps	= 4;		/* point size change for integral (== 4 above) */
+double	Intht	= 1.15;		/* ht of integral in ems */
+double	Intbase	= 0.3;		/* base in ems */
+double	Int1h	= 0.4;		/* lower limit left */
+double	Int1v	= 0.2;		/* lower limit down */
+double	Int2h	= 0.05;		/* upper limit right was 8 */
+double	Int2v	= 0.1;		/* upper limit up */
+
+/* matrix.c: */
+
+char	*Matspace = "\\ \\ ";	/* space between matrix columns */
+
+/* over.c: */
+
+double	Overgap	= 0.3;		/* gap between num and denom */
+double	Overwid	= 0.5;		/* extra width of box */
+double	Overline = 0.1;		/* extra length of fraction bar */
+
+/* paren.c* */
+
+double	Parenbase = 0.4;	/* shift of base for even count */
+double	Parenshift = 0.13;	/* how much to shift parens down in left ... */
+				/* ignored unless postscript */
+double	Parenheight = 0.3;	/* extra height above builtups */
+
+/* pile.c: */
+
+double	Pilegap	= 0.4;		/* gap between pile elems */
+double	Pilebase = 0.5;		/* shift base of even # of piled elems */
+
+/* shift.c: */
+
+double	Subbase	= 0.2;		/* subscript base belowe main base */
+double	Supshift = 0.4;		/* superscript .4 up main box */
+char	*Sub1space = "\\|";	/* italic sub roman space */
+char	*Sup1space = "\\|";	/* italic sup roman space */
+char	*Sub2space = "\\^";	/* space after subscripted thing */
+char	*SS1space = "\\^";	/* space before sub in x sub i sup j */
+char	*SS2space = "\\^";	/* space before sup */
+
+/* sqrt.c: */
+	/* sqrt is hard!  punt for now. */
+	/* part of the problem is that every typesetter does it differently */
+	/* and we have several typesetters to run. */
+
+/* text.c: */
+	/* ought to be done by a table */
+
+struct tune {
+	char	*name;
+	char	*cval;
+} tune[]	={
+  /* diacrit.c */
+	"vec_def",	"\\f1\\v'-.5m'\\s-3\\(->\\s0\\v'.5m'\\fP",	/* was \s-2 & .45m */
+	"dyad_def",	"\\f1\\v'-.5m'\\s-3\\z\\(<-\\|\\(->\\s0\\v'.5m'\\fP",
+	"hat_def",	"\\f1\\v'-.05m'\\s+1^\\s0\\v'.05m'\\fP",	/* was .1 */
+	"tilde_def",	"\\f1\\v'-.05m'\\s+1~\\s0\\v'.05m'\\fP",
+	"dot_def",	"\\f1\\v'-.67m'.\\v'.67m'\\fP",
+	"dotdot_def",	"\\f1\\v'-.67m'..\\v'.67m'\\fP",
+	"utilde_def",	"\\f1\\v'1.0m'\\s+2~\\s-2\\v'-1.0m'\\fP",
+  /* funny.c */
+	"sum_def",	"\\|\\v'.3m'\\s+5\\(*S\\s-5\\v'-.3m'\\|",
+	"union_def",	"\\|\\v'.3m'\\s+5\\(cu\\s-5\\v'-.3m'\\|",
+	"inter_def",	"\\|\\v'.3m'\\s+5\\(ca\\s-5\\v'-.3m'\\|",
+	"prod_def",	"\\|\\v'.3m'\\s+5\\(*P\\s-5\\v'-.3m'\\|",
+  /* integral.c */
+	"int_def",	"\\v'.1m'\\s+4\\(is\\s-4\\v'-.1m'",
+	0, 0
+};
+
+tbl	*ftunetbl[TBLSIZE];	/* user-defined names */
+
+char *ftunes[] ={	/* this table intentionally left small */
+	"Subbase",
+	"Supshift",
+	0
+};
+
+void init_tune(void)
+{
+	int i;
+
+	for (i = 0; tune[i].name != NULL; i++)
+		install(deftbl, tune[i].name, tune[i].cval, 0);
+	for (i = 0; ftunes[i] != NULL; i++)
+		install(ftunetbl, ftunes[i], (char *) 0, 0);
+}
+
+#define eq(s, t) (strcmp(s,t) == 0)
+
+void ftune(char *s, char *t)	/* brute force for now */
+{
+	double f = atof(t);
+	double *target;
+
+	while (*t == ' ' || *t == '\t')
+		t++;
+	if (eq(s, "Subbase"))
+		target = &Subbase;
+	else if (eq(s, "Supshift"))
+		target = &Supshift;
+	if (t[0] == '+' || t[0] == '-')
+		*target += f;
+	else
+		*target = f;
+}
diff --git a/src/cmd/eqn/y.tab.h b/src/cmd/eqn/y.tab.h
new file mode 100644
index 00000000..1f6d3c71
--- /dev/null
+++ b/src/cmd/eqn/y.tab.h
@@ -0,0 +1,57 @@
+#define	CONTIG	57346
+#define	QTEXT	57347
+#define	SPACE	57348
+#define	THIN	57349
+#define	TAB	57350
+#define	MATRIX	57351
+#define	LCOL	57352
+#define	CCOL	57353
+#define	RCOL	57354
+#define	COL	57355
+#define	ABOVE	57356
+#define	MARK	57357
+#define	LINEUP	57358
+#define	SUM	57359
+#define	INT	57360
+#define	PROD	57361
+#define	UNION	57362
+#define	INTER	57363
+#define	DEFINE	57364
+#define	TDEFINE	57365
+#define	NDEFINE	57366
+#define	DELIM	57367
+#define	GSIZE	57368
+#define	GFONT	57369
+#define	INCLUDE	57370
+#define	IFDEF	57371
+#define	DOTEQ	57372
+#define	DOTEN	57373
+#define	FROM	57374
+#define	TO	57375
+#define	OVER	57376
+#define	SQRT	57377
+#define	SUP	57378
+#define	SUB	57379
+#define	SIZE	57380
+#define	FONT	57381
+#define	ROMAN	57382
+#define	ITALIC	57383
+#define	BOLD	57384
+#define	FAT	57385
+#define	UP	57386
+#define	DOWN	57387
+#define	BACK	57388
+#define	FWD	57389
+#define	LEFT	57390
+#define	RIGHT	57391
+#define	DOT	57392
+#define	DOTDOT	57393
+#define	HAT	57394
+#define	TILDE	57395
+#define	BAR	57396
+#define	LOWBAR	57397
+#define	HIGHBAR	57398
+#define	UNDER	57399
+#define	VEC	57400
+#define	DYAD	57401
+#define	UTILDE	57402