plan9 man page for sleep

SLEEP(2)							System Calls Manual							  SLEEP(2)

NAME
       sleep, alarm - delay, ask for delayed note

SYNOPSIS
       #include <u.h>
       #include <libc.h>

       int sleep(long millisecs)

       long alarm(unsigned long millisecs)

DESCRIPTION
       Sleep  suspends	the  current process for the number of milliseconds specified by the argument.	The actual suspension time may be a little
       more or less than the requested time. If millisecs is 0, the process gives up the CPU if another process is waiting to run, returning imme-
       diately if not.	Sleep returns -1 if interrupted, 0 otherwise.

       Alarm causes an alarm note (see notify(2)) to be sent to the invoking process after the number of milliseconds given by the argument.  Suc-
       cessive calls to alarm reset the alarm clock.  A zero argument clears the alarm.  The return value is the amount of time previously remain-
       ing in the alarm clock.

SOURCE
       /sys/src/libc/9syscall

SEE ALSO
       intro(2)

DIAGNOSTICS
       These functions set errstr.

																	  SLEEP(2)