1
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
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
|
<head>
<title>setjmp(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>SETJMP(3)</b><td align=right><b>SETJMP(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>
setjmp, longjmp, notejmp – non-local goto<br>
</table>
<p><font size=+1><b>SYNOPSIS </b></font><br>
<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>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>int setjmp(jmp_buf env)
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>void longjmp(jmp_buf env, int val)
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>void notejmp(void *uregs, jmp_buf env, int val)<br>
</font></tt>
</table>
<p><font size=+1><b>DESCRIPTION </b></font><br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
These routines are useful for dealing with errors and interrupts
encountered in a low-level subroutine of a program.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<i>Setjmp</i> saves its stack environment in <i>env</i> for later use by <i>longjmp</i>.
It returns value 0.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<i>Longjmp</i> restores the environment saved by the last call of <i>setjmp</i>.
It then causes execution to continue as if the call of <i>setjmp</i>
had just returned with value <i>val</i>. The invoker of <i>setjmp</i> must not
itself have returned in the interim. All accessible data have
values as of the time <i>longjmp</i> was called.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<i>Notejmp</i> is the same as <i>longjmp</i> except that it is to be called
from within a note handler (see <a href="../man3/notify.html"><i>notify</i>(3)</a>). The <i>uregs</i> argument
should be the first argument passed to the note handler.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<i>Setjmp</i> and <i>longjmp</i> can also be used to switch stacks.<br>
</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/lib9/jmp.c<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/notify.html"><i>notify</i>(3)</a><br>
</table>
<p><font size=+1><b>BUGS </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>
<i>Notejmp</i> cannot recover from an address trap or bus error (page
fault) on the 680x0 architectures.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
To avoid name conflicts with the underlying system, <i>setjmp</i>, <i>longjmp</i>,
<i>notejmp</i>, and <i>jmp_buf</i> are preprocessor macros defined as <i>p9setjmp</i>,
<i>p9longjmp</i>, <i>p9notejmp</i>, and <i>p9jmp_buf</i>; see <a href="../man3/intro.html"><i>intro</i>(3)</a>.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<i>P9setjmp</i> is implemented as a preprocessor macro that calls <i>sigsetjmp</i>
(see Unix’s <i>setjmp</i>(3)).<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>
|