| | 1 | .\" Copyright (c) 1980, 1991, 1993, 1994 |
| | 2 | .\" The Regents of the University of California. All rights reserved. |
| | 3 | .\" |
| | 4 | .\" Redistribution and use in source and binary forms, with or without |
| | 5 | .\" modification, are permitted provided that the following conditions |
| | 6 | .\" are met: |
| | 7 | .\" 1. Redistributions of source code must retain the above copyright |
| | 8 | .\" notice, this list of conditions and the following disclaimer. |
| | 9 | .\" 2. Redistributions in binary form must reproduce the above copyright |
| | 10 | .\" notice, this list of conditions and the following disclaimer in the |
| | 11 | .\" documentation and/or other materials provided with the distribution. |
| | 12 | .\" 4. Neither the name of the University nor the names of its contributors |
| | 13 | .\" may be used to endorse or promote products derived from this software |
| | 14 | .\" without specific prior written permission. |
| | 15 | .\" |
| | 16 | .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| | 17 | .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| | 18 | .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| | 19 | .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| | 20 | .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| | 21 | .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| | 22 | .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| | 23 | .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| | 24 | .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| | 25 | .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| | 26 | .\" SUCH DAMAGE. |
| | 27 | .\" |
| | 28 | .\" @(#)alarm.3 8.2 (Berkeley) 4/19/94 |
| | 29 | .\" $FreeBSD: src/lib/libc/gen/alarm.3,v 1.17 2007/01/09 00:27:52 imp Exp $ |
| | 30 | .\" |
| | 31 | .Dd April 19, 1994 |
| | 32 | .Dt ALARM 3 |
| | 33 | .Os |
| | 34 | .Sh NAME |
| | 35 | .Nm alarm |
| | 36 | .Nd set signal timer alarm |
| | 37 | .Sh LIBRARY |
| | 38 | .Lb libc |
| | 39 | .Sh SYNOPSIS |
| | 40 | .In unistd.h |
| | 41 | .Ft unsigned |
| | 42 | .Fn alarm "unsigned seconds" |
| | 43 | .Sh DESCRIPTION |
| | 44 | .Bf -symbolic |
| | 45 | This interface is made obsolete by |
| | 46 | .Xr setitimer 2 . |
| | 47 | .Ef |
| | 48 | .Pp |
| | 49 | The |
| | 50 | .Fn alarm |
| | 51 | function sets a timer to deliver the signal |
| | 52 | .Dv SIGALRM |
| | 53 | to the calling process after the specified number of |
| | 54 | .Fa seconds . |
| | 55 | If an alarm has already been set with |
| | 56 | .Fn alarm |
| | 57 | but has not been delivered, another call to |
| | 58 | .Fn alarm |
| | 59 | will supersede the prior call. |
| | 60 | The request |
| | 61 | .Fn alarm "0" |
| | 62 | voids the current |
| | 63 | alarm and the signal SIGALRM will not be delivered. |
| | 64 | .Pp |
| | 65 | Due to |
| | 66 | .Xr setitimer 2 |
| | 67 | restriction the maximum number of |
| | 68 | .Fa seconds |
| | 69 | allowed is 100000000. |
| | 70 | .Sh RETURN VALUES |
| | 71 | The return value of |
| | 72 | .Fn alarm |
| | 73 | is the amount of time left on the timer from a previous call to |
| | 74 | .Fn alarm . |
| | 75 | If no alarm is currently set, the return value is 0. |
| | 76 | .Sh SEE ALSO |
| | 77 | .Xr setitimer 2 , |
| | 78 | .Xr sigaction 2 , |
| | 79 | .Xr sigpause 2 , |
| | 80 | .Xr sigvec 2 , |
| | 81 | .Xr signal 3 , |
| | 82 | .Xr sleep 3 , |
| | 83 | .Xr ualarm 3 , |
| | 84 | .Xr usleep 3 |
| | 85 | .\" .Sh STANDARDS |
| | 86 | .\" The |
| | 87 | .\" .Fn alarm |
| | 88 | .\" function conforms to |
| | 89 | .\" .St -p1003.1-90 . |
| | 90 | .Sh HISTORY |
| | 91 | An |
| | 92 | .Fn alarm |
| | 93 | function appeared in |
| | 94 | .At v7 . |
projects / apple / libc.git / blame_incremental