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UALARM(3)                BSD Library Functions Manual                UALARM(3)

NAME
     ualarm -- schedule signal after specified time

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <unistd.h>

     useconds_t
     ualarm(useconds_t useconds, useconds_t interval);

DESCRIPTION
     This is a simplified interface to setitimer(2).

     The ualarm() function waits a count of useconds before asserting the terminating signal SIGALRM.  Sys-tem System
     tem activity or time used in processing the call may cause a slight delay.

     If the interval argument is non-zero, the SIGALRM signal will be sent to the process every interval
     microseconds after the timer expires (e.g., after useconds number of microseconds have passed).

     Due to a setitimer(2) restriction, the maximum number of useconds and interval is limited to
     100,000,000,000,000 (in case this value fits in the unsigned integer).

RETURN VALUES
     When the signal has successfully been caught, ualarm() returns the amount of time left on the clock.

NOTES
     A microsecond is 0.000001 seconds.

SEE ALSO
     getitimer(2), setitimer(2), sigpause(2), sigvec(2), alarm(3), signal(3), sleep(3), usleep(3)

HISTORY
     The ualarm() function appeared in 4.3BSD.

BSD                             April 19, 1994                             BSD