xref: /csrg-svn/lib/libc/gen/ualarm.3 (revision 66960)
161111Sbostic.\" Copyright (c) 1986, 1991, 1993
261111Sbostic.\"	The Regents of the University of California.  All rights reserved.
325789Smckusick.\"
448352Scael.\" %sccs.include.redist.man%
525789Smckusick.\"
6*66960Sbostic.\"     @(#)ualarm.3	8.2 (Berkeley) 04/19/94
748352Scael.\"
848352Scael.Dd
948352Scael.Dt UALARM 3
1048352Scael.Os BSD 4.3
1148352Scael.Sh NAME
1248352Scael.Nm ualarm
1348352Scael.Nd schedule signal after specified time
1448352Scael.Sh SYNOPSIS
1548352Scael.Fd #include <unistd.h>
1648352Scael.Ft u_int
1748352Scael.Fn ualarm "u_int microseconds" "u_int interval"
1848352Scael.Sh DESCRIPTION
1948352Scael.Bf -symbolic
2025789SmckusickThis is a simplified interface to setitimer(2).
2148352Scael.Ef
2248352Scael.Pp
2348352ScaelThe
2448352Scael.Fn ualarm
2548352Scaelfunction
2648352Scaelwaits a count of
2748352Scael.Ar microseconds
2848352Scaelbefore asserting the terminating signal
2948352Scael.Dv SIGALRM .
3048352ScaelSystem activity or time used in processing the call may cause a slight
3148352Scaeldelay.
3248352Scael.Pp
3325789SmckusickIf the
3448352Scael.Fa interval
3548352Scaelargument is non-zero, the
3648352Scael.Dv SIGALRM
3748352Scaelsignal will be sent
3825789Smckusickto the process every
3948352Scael.Fa interval
4025789Smckusickmicroseconds after the timer expires (e.g. after
4148352Scael.Fa value
4225789Smckusickmicroseconds have passed).
4348352Scael.Sh RETURN VALUES
4448352ScaelWhen the signal has successfully been caught,
4548352Scael.Fn alarm
4648352Scaelreturns the amount of time left on the clock.
47*66960SbosticThe maximum number of
4848352Scael.Ar microseconds
4948352Scaelallowed
5048352Scaelis 2147483647.
5148352Scael.Sh SEE ALSO
5248352Scael.Xr getitimer 2 ,
5348352Scael.Xr setitimer 2 ,
5448352Scael.Xr sigpause 2 ,
5548352Scael.Xr sigvec 2 ,
5648352Scael.Xr signal 3 ,
5748352Scael.Xr sleep 3 ,
5848352Scael.Xr alarm 3 ,
5948352Scael.Xr usleep 3
6048352Scael.Sh HISTORY
6148352ScaelThe
6248352Scael.Fn ualarm
6348352Scaelfunction appeared in
6448352Scael.Bx 4.3 .
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