'\" te
.\"  Copyright 1989 AT&T  Copyright (c) 1998, Sun Microsystems, Inc.  All Rights Reserved
.TH ssignal 3C "29 Dec 1996" "SunOS 5.11" "Standard C Library Functions"
.SH NAME
ssignal, gsignal \- software signals
.SH SYNOPSIS
.LP
.nf
#include <signal.h>

\fBvoid\fR(\fB*ssignal\fR (\fBint\fR \fIsig\fR, \fBint\fR (*\fIaction\fR)(\fBint\fR)))(\fBint\fR);
.fi

.LP
.nf
\fBint\fR \fBgsignal\fR(\fBint\fR \fIsig\fR);
.fi

.SH DESCRIPTION
.sp
.LP
The \fBssignal()\fR and \fBgsignal()\fR functions implement a software facility similar to \fBsignal\fR(3C). This facility is made available to users for their own purposes.
.SS "ssignal(\|)"
.sp
.LP
Software signals made available to users are associated with integers in the inclusive range 1 through 17. A call to \fBssignal()\fR associates a procedure, \fIaction\fR, with the software signal \fIsig\fR; the software signal, \fIsig\fR, is raised by a call to \fBgsignal()\fR. Raising a software signal causes the action established for that signal to be taken.
.sp
.LP
The first argument to \fBssignal()\fR is a number identifying the type of signal for which an action is to be established. The second argument defines the action; it is either the name of a (user-defined) \fIaction\fR \fIfunction\fR or one of the manifest constants \fBSIG_DFL\fR (default) or \fBSIG_IGN\fR (ignore). The \fBssignal()\fR function returns the action previously established for that signal type; if no action has been established or the signal number is illegal, \fBssignal()\fR returns \fBSIG_DFL\fR.
.SS "gsignal(\|)"
.sp
.LP
The \fBgsignal()\fR raises the signal identified by its argument, \fIsig\fR.
.sp
.LP
If an action function has been established for \fIsig\fR, then that action is reset to \fBSIG_DFL\fR and the action function is entered with argument \fIsig\fR. The \fBgsignal()\fR function returns the value returned to it by the action function.
.sp
.LP
If the action for \fIsig\fR is \fBSIG_IGN\fR, \fBgsignal()\fR returns the value 1 and takes no other action.
.sp
.LP
If the action for \fIsig\fR is \fBSIG_DFL\fR, \fBgsignal()\fR returns the value 0 and takes no other action.
.sp
.LP
If \fIsig\fR has an illegal value or no action was ever specified for \fIsig\fR, \fBgsignal()\fR returns the value 0 and takes no other action.
.SH ATTRIBUTES
.sp
.LP
See \fBattributes\fR(5) for descriptions of the following attributes:
.sp

.sp
.TS
tab() box;
cw(2.75i) |cw(2.75i) 
lw(2.75i) |lw(2.75i) 
.
ATTRIBUTE TYPEATTRIBUTE VALUE
_
MT-LevelUnsafe
.TE

.SH SEE ALSO
.sp
.LP
\fBraise\fR(3C), \fBsignal\fR(3C), \fBattributes\fR(5)