NAME
sigemptyset,
sigfillset, sigaddset,
sigdelset, sigismember
— manipulate signal
sets
SYNOPSIS
#include
<signal.h>
int
sigemptyset(sigset_t
*set);
int
sigfillset(sigset_t
*set);
int
sigaddset(sigset_t
*set, int
signo);
int
sigdelset(sigset_t
*set, int
signo);
int
sigismember(const
sigset_t *set, int
signo);
DESCRIPTION
These functions manipulate signal sets stored in a
sigset_t. Either
sigemptyset()
or sigfillset() must be called for every object of
type sigset_t before any other use of the object.
sigemptyset() and
sigfillset() are provided as macros, but actual
functions are available if their names are undefined (with #undef
name).
The
sigemptyset()
function initializes a signal set to be empty.
sigfillset()
initializes a signal set to contain all signals.
sigaddset()
adds the specified signal signo to the signal set.
sigdelset()
deletes the specified signal signo from the signal
set.
sigismember()
returns whether a specified signal signo is contained
in the signal set.
RETURN VALUES
The sigismember() function returns 1 if
the signal is a member of the set and 0 otherwise. The other functions
return 0 upon success. A -1 return value indicates an error occurred and the
global variable errno is set to indicate the
reason.
ERRORS
These functions may fail if one of the following occurs:
- [
EINVAL] - The specified signal signo is not a valid signal number.
SEE ALSO
kill(2), sigaction(2), sigpending(2), sigprocmask(2), sigsuspend(2)
STANDARDS
These functions are defined by IEEE Std 1003.1-1990 (“POSIX.1”).