.\" @(#)alarm.3f 1.4 86/01/02 SMI; from UCB 4.2 .TH ALARM 3F "98/09/16" .SH NAME alarm \- execute a subroutine after a specified time .SH SYNOPSIS .\" .IX alarm "" \fLalarm\fP .IX "delay execution" .\" .B integer*4 function alarm (time, sbrtn) .br .B integer*4 time .br .B external sbrtn .SH USAGE .B integer*4 time /8/ .br .B external sbrtn .br .B nseconds = alarm(time,sbrtn) .SH DESCRIPTION This routine arranges for subroutine .I sbrtn to be called after .I time seconds. If .I time is 0, the alarm is turned off, and no routine is called. The returned value is the time remaining on the last alarm. .SH RESTRICTIONS A subroutine cannot pass its own name to .BR alarm . .LP The .B alarm routine generates signals that could interfere with any I/O. The called routine, .BR sbrtn , must not do any I/O itself. .LP Calling .B alarm() from a parallelized or multi-threaded program may have unpredictable results. .SH FILES .B libF77.a .SH "SEE ALSO" .BR alarm (2), .BR sleep (3F), .BR signal (3F)