svcadm(8)을 검색하려면 섹션에서 8 을 선택하고, 맨 페이지 이름에 svcadm을 입력하고 검색을 누른다.
signal(3c)
signal(3C) Standard C Library Functions signal(3C)
NAME
signal, sigset, sighold, sigrelse, sigignore, sigpause - simplified
signal management for application processes
SYNOPSIS
#include <signal.h>
void (*signal(int sig, void (*disp)(int)))(int);
void (*sigset(int sig, void (*disp)(int)))(int);
int sighold(int sig);
int sigrelse(int sig);
int sigignore(int sig);
int sigpause(int sig);
DESCRIPTION
These functions provide simplified signal management for application
processes. See signal.h(3HEAD) for an explanation of general signal
concepts.
The signal() and sigset() functions modify signal dispositions. The sig
argument specifies the signal, which may be any signal except SIGKILL
and SIGSTOP. The disp argument specifies the signal's disposition,
which may be SIG_DFL, SIG_IGN, or the address of a signal handler. If
signal() is used, disp is the address of a signal handler, and sig is
not SIGILL, SIGTRAP, or SIGPWR, the system first sets the signal's dis‐
position to SIG_DFL before executing the signal handler. If sigset() is
used and disp is the address of a signal handler, the system adds sig
to the calling process's signal mask before executing the signal han‐
dler; when the signal handler returns, the system restores the calling
process's signal mask to its state prior to the delivery of the signal.
In addition, if sigset() is used and disp is equal to SIG_HOLD, sig is
added to the calling process's signal mask and the signal's disposition
remains unchanged.
The sighold() function adds sig to the calling process's signal mask.
The sigrelse() function removes sig from the calling process's signal
mask.
The sigignore() function sets the disposition of sig to SIG_IGN.
The sigpause() function removes sig from the calling process's signal
mask and suspends the calling process until a signal is received.
RETURN VALUES
Upon successful completion, signal() returns the signal's previous dis‐
position. Otherwise, it returns SIG_ERR and sets errno to indicate the
error.
Upon successful completion, sigset() returns SIG_HOLD if the signal had
been blocked or the signal's previous disposition if it had not been
blocked. Otherwise, it returns SIG_ERR and sets errno to indicate the
error.
Upon successful completion, sighold(), sigrelse(), sigignore(), and
sigpause(), return 0. Otherwise, they return −1 and set errno to indi‐
cate the error.
ERRORS
These functions fail if:
EINTR A signal was caught during the execution of sigpause().
EINVAL The value of the sig argument is not a valid signal or is
equal to SIGKILL or SIGSTOP.
USAGE
The sighold() function used in conjunction with sigrelse() or sig‐
pause() may be used to establish critical regions of code that require
the delivery of a signal to be temporarily deferred.
If signal() or sigset() is used to set SIGCHLD's disposition to a sig‐
nal handler, SIGCHLD will not be sent when the calling process's chil‐
dren are stopped or continued.
If any of the above functions are used to set SIGCHLD's disposition to
SIG_IGN, the calling process's child processes will not create zombie
processes when they terminate (see exit(2)). If the calling process
subsequently waits for its children, it blocks until all of its chil‐
dren terminate; it then returns −1 with errno set to ECHILD (see
wait(3C) and waitid(2)).
The system guarantees that if more than one instance of the same signal
is generated to a process, at least one signal will be received. It
does not guarantee the reception of every generated signal.
ATTRIBUTES
See attributes(7) for descriptions of the following attributes:
tab() box; cw(2.75i) |cw(2.75i) lw(2.75i) |lw(2.75i) ATTRIBUTE TYPEAT‐
TRIBUTE VALUE _ Interface StabilityCommitted _ MT-LevelAsync-Signal-
Safe _ StandardSee standards(7).
SEE ALSO
exit(2), kill(2), pause(2), sigaction(2), sigsend(2), waitid(2),
wait(3C), signal.h(3HEAD), attributes(7), standards(7)
HISTORY
The sighold(), sigignore(), sigrelse(), and sigset() functions were
added in Solaris 2.0.
The signal() and sigpause() functions have been included in all Sun and
Oracle releases of Solaris.
Oracle Solaris 11.4 27 Aug 2025 signal(3C)