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@(#)ualarm.3 8.2 (Berkeley) 4/19/94
.Dd April 19, 1994 .Dt UALARM 3 .Os BSD 4.3 .Sh NAME .Nm ualarm .Nd schedule signal after specified time .Sh SYNOPSIS .Fd #include <unistd.h> .Ft u_int .Fn ualarm "u_int microseconds" "u_int interval" .Sh DESCRIPTION f -symbolic This is a simplified interface to setitimer(2). .Ef
p The .Fn ualarm function waits a count of .Ar microseconds before asserting the terminating signal .Dv SIGALRM . System activity or time used in processing the call may cause a slight delay.
p If the .Fa interval argument is non-zero, the .Dv SIGALRM signal will be sent to the process every .Fa interval microseconds after the timer expires (e.g. after .Fa value microseconds have passed). .Sh RETURN VALUES When the signal has successfully been caught, .Fn alarm returns the amount of time left on the clock. The maximum number of .Ar microseconds allowed is 2147483647. .Sh SEE ALSO .Xr getitimer 2 , .Xr setitimer 2 , .Xr sigpause 2 , .Xr sigvec 2 , .Xr signal 3 , .Xr sleep 3 , .Xr alarm 3 , .Xr usleep 3 .Sh HISTORY The .Fn ualarm function appeared in x 4.3 .