ualarm(3) [netbsd man page]

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 microseconds, useconds_t interval);

DESCRIPTION

     This is a simplified interface to setitimer(2).

     The ualarm() function waits a count of microseconds before asserting the terminating signal SIGALRM.  System activity or time used in pro-
     cessing 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 microseconds microseconds have passed).

RETURN VALUES

     When the signal has successfully been caught, ualarm() returns the amount of time left on the clock.  The maximum number of microseconds
     allowed is 2147483647.  If there is an error setting the timer, ualarm() returns ((useconds_t) -1).

SEE ALSO

     getitimer(2), setitimer(2), sigaction(2), sigsuspend(2), alarm(3), signal(3), sigvec(3), sleep(3), usleep(3)

STANDARDS

     The ualarm() function conforms to IEEE Std 1003.1-2001 (``POSIX.1'').  However, the later IEEE Std 1003.1-2008 (``POSIX.1'') revision removed
     the function from the specification.

HISTORY

     The ualarm() function appeared in 4.3BSD.

BSD
								    May 2, 2011 							       BSD

ualarm(3C)						   Standard C Library Functions 						ualarm(3C)

NAME

       ualarm - schedule signal after interval in microseconds

SYNOPSIS

       #include <unistd.h>

       useconds_t ualarm(useconds_t useconds, useconds_t interval);

DESCRIPTION

       The  ualarm()  function causes the SIGALRM signal to be generated for the calling process after the number of real-time microseconds speci-
       fied by the useconds argument has elapsed.  When the interval argument is non-zero, repeated timeout notification occurs with a	period	in
       microseconds specified by the interval argument. If the notification signal, SIGALRM, is not caught or ignored, the calling process is ter-
       minated.

       Because of scheduling delays, resumption of execution when the signal is caught may be delayed an arbitrary amount of time.

       Interactions between ualarm() and either alarm(2) or sleep(3C) are unspecified.

RETURN VALUES

       The ualarm() function returns the number of microseconds remaining from the previous ualarm() call.  If	no  timeouts  are  pending  or	if
       ualarm() has not previously been called, ualarm() returns 0.

ERRORS

       No errors are defined.

USAGE

       The ualarm() function is a simplified interface to setitimer(2), and uses the ITIMER_REAL interval timer.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Standard			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       alarm(2), setitimer(2), sighold(3C), signal(3C), sleep(3C), usleep(3C), attributes(5), standards(5)

SunOS 5.10							    14 Aug 2002 							ualarm(3C)