|USLEEP(3)||Library Functions Manual||USLEEP(3)|
usleep() function suspends execution
of the calling process until either microseconds
microseconds have elapsed or a signal is delivered to the process and its
action is to invoke a signal-catching function or to terminate the process.
The suspension time may be longer than requested due to the scheduling of
other activity by the system.
This function is implemented using
nanosleep(2) by pausing for
microseconds microseconds or until a signal occurs.
Consequently, in this implementation, sleeping has no effect on the state of
process timers, and there is no special handling for
usleep() function returns the value 0 if successful; otherwise the value -1 is returned and the global variable errno is set to indicate the error.
usleep() function will fail if:
usleep() function conforms to X/Open Portability Guide Issue 4, Version 2 (“XPG4.2”).
usleep() function appeared in 4.3BSD.
usleep() return an error if microseconds is greater than or equal to 1,000,000. Portable applications should be written with this limitation in mind.
|June 5, 2013||OpenBSD-current|