BSD Functions for Blocking Signals
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- Macro: int sigmask (int SIGNUM)
This macro returns a signal mask that has the bit for signal SIGNUM
set. You can bitwise-OR the results of several calls to `sigmask'
together to specify more than one signal. For example,
(sigmask (SIGTSTP) | sigmask (SIGSTOP)
| sigmask (SIGTTIN) | sigmask (SIGTTOU))
specifies a mask that includes all the job-control stop signals.
- Function: int sigblock (int MASK)
This function is equivalent to `sigprocmask' (Note:Process Signal
Mask) with a HOW argument of `SIG_BLOCK': it adds the signals
specified by MASK to the calling process's set of blocked signals.
The return value is the previous set of blocked signals.
- Function: int sigsetmask (int MASK)
This function equivalent to `sigprocmask' (Note:Process Signal
Mask) with a HOW argument of `SIG_SETMASK': it sets the calling
process's signal mask to MASK. The return value is the previous
set of blocked signals.
- Function: int sigpause (int MASK)
This function is the equivalent of `sigsuspend' (Note:Waiting for
a Signal): it sets the calling process's signal mask to MASK,
and waits for a signal to arrive. On return the previous set of
blocked signals is restored.