| 1 | .\" Copyright (c) 1980 Regents of the University of California. |
| 2 | .\" All rights reserved. The Berkeley software License Agreement |
| 3 | .\" specifies the terms and conditions for redistribution. |
| 4 | .\" |
| 5 | .\" @(#)alarm.3 6.3 (Berkeley) %G% |
| 6 | .\" |
| 7 | .TH ALARM 3C "" |
| 8 | .UC 4 |
| 9 | .SH NAME |
| 10 | alarm \- schedule signal after specified time |
| 11 | .SH SYNOPSIS |
| 12 | .nf |
| 13 | .B alarm(seconds) |
| 14 | .B unsigned seconds; |
| 15 | .fi |
| 16 | .SH DESCRIPTION |
| 17 | .ft B |
| 18 | This interface is made obsolete by setitimer(2). |
| 19 | .ft R |
| 20 | .PP |
| 21 | .I Alarm |
| 22 | causes signal SIGALRM, see |
| 23 | .IR sigvec (2), |
| 24 | to be sent to the invoking process |
| 25 | in a number of seconds given by the argument. |
| 26 | Unless caught or ignored, the signal terminates the process. |
| 27 | .PP |
| 28 | Alarm requests are not stacked; successive calls reset the alarm clock. |
| 29 | If the argument is 0, any alarm request is canceled. |
| 30 | Because of scheduling delays, |
| 31 | resumption of execution of when the signal is |
| 32 | caught may be delayed an arbitrary amount. |
| 33 | The longest specifiable delay time is 2147483647 seconds. |
| 34 | .PP |
| 35 | The return value is the amount of time previously remaining in the alarm clock. |
| 36 | .SH "SEE ALSO" |
| 37 | sigpause(2), sigvec(2), signal(3C), sleep(3), ualarm(3), usleep(3) |