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ualarm(3) [bsd man page]

UALARM(3)						     Library Functions Manual							 UALARM(3)

NAME
ualarm - schedule signal after specified time SYNOPSIS
unsigned ualarm(value, interval) unsigned value; unsigned interval; DESCRIPTION
This is a simplified interface to setitimer(2). Ualarm causes signal SIGALRM, see signal(3C), to be sent to the invoking process in a number of microseconds given by the value argument. Unless caught or ignored, the signal terminates the process. 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 value microseconds have passed). Because of scheduling delays, resumption of execution of when the signal is caught may be delayed an arbitrary amount. The longest speci- fiable delay time (on the vax) is 2147483647 microseconds. The return value is the amount of time previously remaining in the alarm clock. SEE ALSO
getitimer(2), setitimer(2), sigpause(2), sigvec(2), signal(3C), sleep(3), alarm(3), usleep(3) NOTES (PDP-11) On the PDP-11, setitimer(2) rounds the number of microseconds up to seconds resolution, therefore ualarm doesn't give you any more resolu- tion than alarm(3). 4.3 Berkeley Distribution August 26, 1988 UALARM(3)

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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 5.11 14 Aug 2002 ualarm(3C)
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