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Old 10-23-2010
Blocking signals

I know how to add signal to a set. But what if I want to add 2 or 3 signals to the set.
I know I can use sigaddset (&set,SIGBUS)....but what if I want to add SIGBUS and SIGALRM at once. Do i have to do it like this..
Code:
sigaddset (&set,SIGBUS);
sigaddset (&set,SIGALRM);

Is there another way to do this?. Also is it possible to individually unblock signals in the set. I know that by calling
[code]
sigprocmask(SIG_UNBLOCK......) you can unblock all signals that are block in the set.But what if you want to only unblock one signal in the set.

Last edited by joker40; 10-24-2010 at 12:32 PM.. Reason: adding something
 

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SIGSETOPS(3)						     Linux Programmer's Manual						      SIGSETOPS(3)

NAME
sigemptyset, sigfillset, sigaddset, sigdelset, sigismember - POSIX signal set operations. SYNOPSIS
#include <signal.h> int sigemptyset(sigset_t *set); int sigfillset(sigset_t *set); int sigaddset(sigset_t *set, int signum); int sigdelset(sigset_t *set, int signum); int sigismember(const sigset_t *set, int signum); DESCRIPTION
The sigsetops(3) functions allow the manipulation of POSIX signal sets. sigemptyset initializes the signal set given by set to empty, with all signals excluded from the set. sigfillset initializes set to full, including all signals. sigaddset and sigdelset add and delete respectively signal signum from set. sigismember tests whether signum is a member of set. RETURN VALUE
sigemptyset, sigfillset, sigaddset and sigdelset return 0 on success and -1 on error. sigismember returns 1 if signum is a member of set, 0 if signum is not a member, and -1 on error. ERRORS
EINVAL sig is not a valid signal. CONFORMING TO
POSIX SEE ALSO
sigaction(2), sigpending(2), sigprocmask(2), sigsuspend(2) Linux 1.0 1994-09-24 SIGSETOPS(3)

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