NAME
pause — suspend
the thread until a signal is received
SYNOPSIS
#include
<unistd.h>
int pause(void);
DESCRIPTION
The pause () function shall suspend the
calling thread until delivery of a signal whose action is either to execute
a signal-catching function or to terminate the process.
If the action is to terminate the process,
pause () shall not return.
If the action is to execute a signal-catching function,
pause () shall return after the signal-catching
function returns.
RETURN VALUE
Since pause () suspends thread execution
indefinitely unless interrupted by a signal, there is no successful
completion return value. A value of -1 shall be returned and
errno
set to indicate the error.
ERRORS
The pause () function shall fail if:
- [EINTR]
- A signal is caught by the calling process and control is returned from the signal-catching function.
EXAMPLES
None.
APPLICATION USAGE
Many common uses of pause () have timing
windows. The scenario involves checking a condition related to a signal and,
if the signal has not occurred, calling pause ().
When the signal occurs between the check and the call to
pause (), the process often blocks indefinitely. The
sigprocmask(3) and sigsuspend(3)
functions can be used to avoid this type of problem.
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
XBD <unistd.h>
CHANGE HISTORY
First released in Issue 1. Derived from Issue 1 of the SVID.
Issue 5
The DESCRIPTION is updated for alignment with the POSIX Threads Extension.
Issue 6
The APPLICATION USAGE section is added.