4.4BSD/usr/src/lib/libc/gen/alarm.3

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.\"     @(#)alarm.3	8.1 (Berkeley) 6/4/93
.\"
.Dd June 4, 1993
.Dt ALARM 3
.Os BSD 4
.Sh NAME
.Nm alarm
.Nd set signal timer alarm
.Sh SYNOPSIS
.Fd #include <unistd.h>
.Ft u_int
.Fn alarm "u_int seconds"
.Sh DESCRIPTION
.Bf -symbolic
This interface is made obsolete by setitimer(2).
.Ef
.Pp
The
.Fn alarm
function
waits a count of
.Ar seconds
before asserting the terminating signal
.Dv SIGALRM .
When the signal has successfully been caught,
.Fn alarm
returns the amount of time left on the clock.
The maximum mumber of
.Ar seconds
allowed
is 2147483647.
.Pp
If an alarm has been set with
.Fn alarm ,
another call to
.Fn alarm
will superceed the prior call.
The request
.Fn alarm "0"
voids the current
alarm.
.Sh SEE ALSO
.Xr sigaction 2 ,
.Xr setitimer 2 ,
.Xr sigpause 2 ,
.Xr sigvec 2 ,
.Xr signal 3 ,
.Xr sleep 3 ,
.Xr ualarm 3 ,
.Xr usleep 3
.Sh HISTORY
An
.Fn alarm
function appeared in 
.At v7 .