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diff --git a/man/man3/ioproc.html b/man/man3/ioproc.html new file mode 100644 index 00000000..092bac91 --- /dev/null +++ b/man/man3/ioproc.html @@ -0,0 +1,211 @@ +<head> +<title>ioproc(3) - Plan 9 from User Space</title> +<meta content="text/html; charset=utf-8" http-equiv=Content-Type> +</head> +<body bgcolor=#ffffff> +<table border=0 cellpadding=0 cellspacing=0 width=100%> +<tr height=10><td> +<tr><td width=20><td> +<tr><td width=20><td><b>IOPROC(3)</b><td align=right><b>IOPROC(3)</b> +<tr><td width=20><td colspan=2> + <br> +<p><font size=+1><b>NAME </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + closeioproc, iocall, ioclose, iointerrupt, iodial, ioopen, ioproc, + ioread, ioread9pmsg, ioreadn, iorecvfd, iosendfd, iosleep, iowrite + – slave I/O processes for threaded programs<br> + +</table> +<p><font size=+1><b>SYNOPSIS </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <tt><font size=+1>#include <u.h><br> + #include <libc.h><br> + #include <thread.h><br> + typedef struct Ioproc Ioproc;<br> + Ioproc* ioproc(void);<br> + int ioclose(Ioproc *io, int fd);<br> + int iodial(Ioproc *io, char *addr, char *local, char *dir, char + *cdfp);<br> + int ioopen(Ioproc *io, char *file, int omode);<br> + long ioread(Ioproc *io, int fd, void *a, long n);<br> + int ioread9pmsg(Ioproc *io, int fd, void *a, uint n);<br> + long ioreadn(Ioproc *io, int fd, void *a, long n);<br> + int iorecvfd(int socket);<br> + int iosendfd(int socket, int fd);<br> + int iosleep(int milli);<br> + long iowrite(Ioproc *io, int fd, void *a, long n);<br> + void iointerrupt(Ioproc *io);<br> + void closeioproc(Ioproc *io);<br> + long iocall(Ioproc *io, long (*op)(va_list *arg), ...);<br> + </font></tt> +</table> +<p><font size=+1><b>DESCRIPTION </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + These routines provide access to I/O in slave procs. Since the + I/O itself is done in a slave proc, other threads in the calling + proc can run while the calling thread waits for the I/O to complete. + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + <i>Ioproc</i> forks a new slave proc and returns a pointer to the <tt><font size=+1>Ioproc</font></tt> + associated with it. <i>Ioproc</i> uses <i>mallocz</i> and <i>proccreate</i>; if either + fails, it calls <i>sysfatal</i> rather than return an error. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + <i>Ioclose</i>, <i>iodial</i>, <i>ioopen</i>, <i>ioread</i>, <i>ioread9pmsg</i>, <i>ioreadn</i>, <i>iorecvfd</i>, + <i>iosendfd</i>, <i>iosleep</i>, and <i>iowrite</i> execute the similarly named library + or system calls (see <a href="../man2/close.html"><i>close</i>(2)</a>, <a href="../man3/dial.html"><i>dial</i>(3)</a>, <a href="../man3/open.html"><i>open</i>(3)</a>, <a href="../man3/read.html"><i>read</i>(3)</a>, <a href="../man3/fcall.html"><i>fcall</i>(3)</a>, + <a href="../man3/sendfd.html"><i>sendfd</i>(3)</a>, and <a href="../man3/sleep.html"><i>sleep</i>(3)</a>) in the slave process associated with + <i>io</i>. It is an error to execute more than one call at a time in + an I/O + proc. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + <i>Iointerrupt</i> interrupts the call currently executing in the I/O + proc. If no call is executing, <i>iointerrupt</i> is a no-op. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + <i>Closeioproc</i> terminates the I/O proc and frees the associated <tt><font size=+1>Ioproc + . + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + <i>Iocall</i> is a primitive that may be used to implement more slave + I/O routines. <i>Iocall</i> arranges for <i>op</i> to be called in <i>io</i>’s proc, + with <i>arg</i> set to the variable parameter list, returning the value + that <i>op</i> returns.<br> + +</table> +<p><font size=+1><b>EXAMPLE </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Relay messages between two file descriptors, counting the total + number of bytes seen:<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <tt><font size=+1>int tot;<br> + void<br> + relaythread(void *v)<br> + {<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + int *fd, n;<br> + char buf[1024];<br> + Ioproc *io;<br> + fd = v;<br> + io = ioproc();<br> + while((n = ioread(io, fd[0], buf, sizeof buf)) > 0){<br> + if(iowrite(io, fd[1], buf, n) != n)<br> + sysfatal("iowrite: %r");<br> + tot += n;<br> + }<br> + closeioproc(io);<br> + + </table> + }<br> + void<br> + relay(int fd0, int fd1)<br> + {<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + int fd[4];<br> + fd[0] = fd[3] = fd0;<br> + fd[1] = fd[2] = fd1;<br> + threadcreate(relaythread, fd, 8192);<br> + threadcreate(relaythread, fd+2, 8192);<br> + + </table> + }<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + + </table> + If the two <i>relaythread</i> instances were running in different procs, + the common access to <i>tot</i> would be unsafe. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + Implement <i>ioread</i>:<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <tt><font size=+1>static long<br> + _ioread(va_list *arg)<br> + {<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + int fd;<br> + void *a;<br> + long n;<br> + fd = va_arg(*arg, int);<br> + a = va_arg(*arg, void*);<br> + n = va_arg(*arg, long);<br> + return read(fd, a, n);<br> + + </table> + }<br> + long<br> + ioread(Ioproc *io, int fd, void *a, long n)<br> + {<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + return iocall(io, _ioread, fd, a, n);<br> + + </table> + }<br> + </font></tt> + </table> + +</table> +<p><font size=+1><b>SOURCE </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <tt><font size=+1>/usr/local/plan9/src/libthread<br> + </font></tt> +</table> +<p><font size=+1><b>SEE ALSO </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <a href="../man3/dial.html"><i>dial</i>(3)</a>, <a href="../man3/open.html"><i>open</i>(3)</a>, <a href="../man3/read.html"><i>read</i>(3)</a>, <a href="../man3/thread.html"><i>thread</i>(3)</a><br> + +</table> +<p><font size=+1><b>BUGS </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <i>Iointerrupt</i> is currently unimplemented.<br> + +</table> + +<td width=20> +<tr height=20><td> +</table> +<!-- TRAILER --> +<table border=0 cellpadding=0 cellspacing=0 width=100%> +<tr height=15><td width=10><td><td width=10> +<tr><td><td> +<center> +<a href="../../"><img src="../../dist/spaceglenda100.png" alt="Space Glenda" border=1></a> +</center> +</table> +<!-- TRAILER --> +</body></html> |