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Diffstat (limited to 'static/unix-v10/man2/alarm.2')
| -rw-r--r-- | static/unix-v10/man2/alarm.2 | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/static/unix-v10/man2/alarm.2 b/static/unix-v10/man2/alarm.2 new file mode 100644 index 00000000..62d16a42 --- /dev/null +++ b/static/unix-v10/man2/alarm.2 @@ -0,0 +1,83 @@ +.TH ALARM 2 +.CT 2 time_man +.SH NAME +alarm, nap, pause \(mi schedule timing delays +.SH SYNOPSIS +.nf +.B unsigned alarm(seconds) +.B unsigned seconds; +.PP +.B void nap(ticks) +.PP +.B void pause() +.fi +.SH DESCRIPTION +.I Alarm +causes signal +.BR SIGALRM , +see +.IR signal (2), +to be sent to the invoking process +in the number of seconds given by the argument. +Unless caught or ignored, the signal terminates the process. +.PP +Alarm requests are not stacked; +successive calls reset the alarm clock. +If the argument is 0, +any alarm request is canceled. +Because the clock has a one second resolution, +the signal may occur up to one second early; +because of scheduling delays, +resumption of execution of when the signal is +caught may be delayed an arbitrary amount. +.PP +The return value is the amount of time +previously remaining in the alarm clock. +.PP +.I Nap +suspends execution of +the current process +for +the specified number of clock ticks. +If +.I ticks +is negative, +it is taken to be zero; +if it is greater than two seconds, +it is taken to be two seconds. +.PP +.I Pause +only returns upon termination of a signal handler started during the +.IR pause . +It is used to give up control while waiting for +a signal, +usually from +.I kill +(see +.IR signal (2)), +.IR alarm (2), +or the terminal driver +.IR ttyld (4). +.SH "SEE ALSO" +.IR kill (1), +.IR signal (2), +.IR setjmp (3), +.IR sleep (3) +.SH BUGS +If the argument to +.I alarm +is greater than 65535, +it is treated as 65535. +.br +If the alarm clock expires +during a call to +.IR alarm , +the return value will be 0, +and the signal will be delivered +immediately after the system call returns. +If the routine calling +.I alarm +saves the return value +and later restores it, +it will disable any alarm +set by the signal handler. |
