Libc-1272.250.1.tar.gz

[apple/libc.git] / gen / FreeBSD / usleep.3

diff --git a/gen/FreeBSD/usleep.3 b/gen/FreeBSD/usleep.3
index e99b773da51ff826173c0670a2b0794b02468ba1..12b9274672474be307175560813566e63e8ea103 100644 (file)
--- a/gen/FreeBSD/usleep.3
+++ b/gen/FreeBSD/usleep.3
@@ -26,7 +26,7 @@
 .\" SUCH DAMAGE.
 .\"
 .\"     @(#)usleep.3   8.1 (Berkeley) 6/4/93
-.\" $FreeBSD: src/lib/libc/gen/usleep.3,v 1.19 2007/01/09 00:27:56 imp Exp $
+.\" $FreeBSD$
 .\"
 .Dd February 13, 1998
 .Dt USLEEP 3
@@ -39,29 +39,37 @@
 .Sh SYNOPSIS
 .In unistd.h
 .Ft int
-.Fo usleep
-.Fa "useconds_t useconds"
-.Fc
+.Fn usleep "useconds_t microseconds"
 .Sh DESCRIPTION
 The
 .Fn usleep
 function suspends execution of the calling thread until either
-.Fa useconds
-microseconds have elapsed
-or a signal is delivered to the thread whose action
-is to invoke a signal-catching function
-or to terminate the thread or process.
-The actual time slept may be longer, due to system latencies
-and possible limitations in the timer resolution of the hardware.
+.Fa 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 or limitations may lengthen the sleep by an indeterminate amount.
 .Pp
-This function is implemented, using
-.Xr nanosleep 2 ,
+This function is implemented using
+.Xr nanosleep 2
 by pausing for
-.Fa useconds
+.Fa microseconds
 microseconds or until a signal occurs.
 Consequently, in this implementation,
-sleeping has no effect on the state of process timers
+sleeping has no effect on the state of process timers,
 and there is no special handling for SIGALRM.
+Also, this implementation does not put a limit on the value of
+.Fa microseconds
+(other than that limited by the size of the
+.Ft useconds_t
+type); some other platforms require it to be less than one million.
+.Sh NOTE
+The
+.Fn usleep
+function is obsolescent.
+Use
+.Xr nanosleep 2
+instead.
 .Sh RETURN VALUES
 .Rv -std usleep
 .Sh ERRORS