#include <signal.h>
void(*signal(int sig,
void (*disp)(int)))(int);
The signal() function is
used to modify signal disposition by handling receipt of the
signal number sig in one of three ways: taking the default
action for the signal, ignoring the signal, or catching the
signal. If the value of disp is SIG_DFL,
default handling for that signal will
occur. If SIGCHLD disposition is changed to a handler
from SIG_DFL and if there are zombie processes, a
SIGCHLD is raised. If the value of disp
is SIG_IGN, the signal is ignored.
Otherwise, disp points to a
function (a signal handler) to be called when that signal occurs.
If disp is the address of a signal handler and
sig is not SIGILL, SIGTRAP,
or SIGPWR, the system first sets the signal's
disposition to SIG_DFL before executing the signal handler.
If signal() is used to set the disposition of
SIGCHLD to a signal handler, SIGCHLD
is not sent when the children of the
calling process are stopped or continued.
If signal() is used to set the disposition of
SIGCHLD to SIG_IGN, the child processes
of the calling process does not create zombie processes when they terminate.
If the calling process subsequently waits for its children, it
blocks until all of its children terminate; it then returns a
value of -1 with errno set to ECHILD.
The sigaction() function provides a more comprehensive
and reliable mechanism for controlling signals; new applications
should use sigaction() rather than
signal().
Refer to api_intro for a discussion of the signals that the NuTCRACKER Platform
supports and their default actions.
- sig
-
Specifies the signal, which may be any signal except
SIGKILL or SIGSTOP.
- disp
-
Points to the signal's disposition, which may be SIG_DFL,
SIG_IGN, or the address of a signal handler.
If successful, signal() returns the signal's previous
disposition. On failure, it returns SIG_ERR and sets
errno to one of the following values:
- EINVAL
-
The value of sig is not a valid
signal or is equal to SIGKILL or SIGSTOP.
POSIX.1 (1996).
MT-Safe.
None.
PTC MKS Toolkit for Professional Developers
PTC MKS Toolkit for Professional Developers 64-Bit Edition
PTC MKS Toolkit for Enterprise Developers
PTC MKS Toolkit for Enterprise Developers 64-Bit Edition
api_intro
- Functions:
- bsd_signal(), kill(), pause(), sigaction(), sighold(), sigignore(), siginterrupt(), sigpause(), sigrelse(), sigset(), wait()
PTC MKS Toolkit 10.5 Documentation Build 40.