sighold() -- System Call (libc)

Place a signal on hold
#include <signal.h>
int sighold (sigtype)
int sigtype;

sighold()  is a  member of  the sigset()  family of  signal-handling system
calls.  It is equivalent to the system call

    sigset(sigtype, SIG_HOLD);

This, in  effect, places  the signal sigtype  ``on hold'' until  the system
call sigrelse()  is invoked for  it.  Only one  ``copy'' of sigtype  can be
held at a time.

Thus,  you can  use sighold()  and  sigrelse() to  defer processing  of the
signal sigtype.  This permits you to protect a  portion of your application
from this signal until it is ready to process it.

See the Lexicon entry for signal()  for a list of recognized signals.  Note
that signal SIGKILL cannot be held.

sighold()  returns zero  if all  went  well.  If  something went  wrong, it
returns -1 and sets errno to an appropriate value.

See Also

libc,
sigignore(),
signal(),
sigpause(),
sigrelse(),
sigset()

Notes

For  more information  on  the sigset()  family  of signal-handling  system
calls, see the Lexicon entry for sigset().

© 2012 by Stephen A. Ness