1997-02-27 07:32:31 +00:00
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.\" Copyright (c) 1980, 1991, 1993, 1994
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.\" The Regents of the University of California. All rights reserved.
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.\"
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.\" Redistribution and use in source and binary forms, with or without
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.\" modification, are permitted provided that the following conditions
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.\" are met:
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.\" 1. Redistributions of source code must retain the above copyright
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.\" notice, this list of conditions and the following disclaimer.
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.\" 2. Redistributions in binary form must reproduce the above copyright
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.\" notice, this list of conditions and the following disclaimer in the
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.\" documentation and/or other materials provided with the distribution.
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.\" 3. All advertising materials mentioning features or use of this software
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.\" must display the following acknowledgement:
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.\" This product includes software developed by the University of
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.\" California, Berkeley and its contributors.
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.\" 4. Neither the name of the University nor the names of its contributors
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.\" may be used to endorse or promote products derived from this software
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.\" without specific prior written permission.
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.\"
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.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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.\" SUCH DAMAGE.
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.\"
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.\" @(#)alarm.3 8.2 (Berkeley) 4/19/94
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.\"
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.TH ALARM 2 "16 January 1997" GNO "System Calls"
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.SH NAME
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.BR alarm
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\- set signal timer alarm
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.SH SYNOPSIS
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.br
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#include <unistd.h>
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.sp 1
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long
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\fBalarm\fR (long \fIseconds\fR);
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.br
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long
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\fBalarm10\fR (long \fItenths\fR);
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.SH DESCRIPTION
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.LP
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The
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.BR alarm
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function
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waits a count of
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.BR seconds
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before asserting the terminating signal
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.BR SIGALRM .
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When the signal has successfully been caught,
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.BR alarm
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returns the amount of time left on the clock.
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.LP
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If an alarm has been set with
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.BR alarm ,
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another call to
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.BR alarm
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will supersede the prior call.
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If
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.IR seconds
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is zero, the alarm timer is disabled.
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.LP
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.BR alarm10
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is identical to
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.BR alarm ,
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except that values are measured in tenths of seconds.
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.SH ERRORS
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No errors are possible.
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.SH STANDARDS
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.BR alarm
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is not quite POSIX conformant in that it uses types of
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.BR long
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rather than
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.BR "unsigned int" .
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.BR alarm10
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is a non-standard function.
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.SH SEE ALSO
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.BR setitimer (2),
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.BR sigpause (2),
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.BR sigvec (2),
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.BR signal (2),
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.BR sleep (3),
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.BR ualarm (3),
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.BR usleep (3)
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.SH HISTORY
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An
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.BR alarm
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1997-10-04 04:40:10 +00:00
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function appeared in Version 7 AT&T UNIX.
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