NAME    [Toc]    [Back]

     usleep -- suspend process execution for an interval measured in microseconds

LIBRARY    [Toc]    [Back]

     Standard C Library (libc, -lc)

SYNOPSIS    [Toc]    [Back]

     #include <unistd.h>

     int
     usleep(useconds_t microseconds);

DESCRIPTION    [Toc]    [Back]

     The 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.  System activity may lengthen the sleep by an
     indeterminate 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    [Toc]    [Back]

     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    [Toc]    [Back]

     The usleep() function will fail if:

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

SEE ALSO    [Toc]    [Back]

     nanosleep(2), sleep(3)

HISTORY    [Toc]    [Back]

     The usleep() function appeared in 4.3BSD.


FreeBSD 5.2.1		       February 13, 1998		 FreeBSD 5.2.1