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USLEEP(3)	       FreeBSD Library Functions Manual		     USLEEP(3)

NAME
     usleep -- suspend thread execution	for an interval	measured in microsec-
     onds

LIBRARY
     Standard C	Library	(libc, -lc)

SYNOPSIS
     #include <unistd.h>

     int
     usleep(useconds_t microseconds);

DESCRIPTION
     The usleep() function suspends execution of the calling thread until ei-
     ther microseconds microseconds have elapsed or a signal is	delivered to
     the thread	and its	action is to invoke a signal-catching function or to
     terminate the process.  System activity may lengthen the sleep by an in-
     determinate amount.

     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 SIGALRM.

RETURN VALUES
     The 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.

ERRORS
     The usleep() function will	fail if:

     [EINTR]		A signal was delivered to the calling thread and its
			action was to invoke a signal-catching function.

SEE ALSO
     nanosleep(2), sleep(3)

HISTORY
     The usleep() function appeared in 4.3BSD.

FreeBSD	13.0		       February	11, 2021		  FreeBSD 13.0

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUES | ERRORS | SEE ALSO | HISTORY

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