April 19, 1994 UALARM 3

### NAME

ualarm - schedule signal after specified time

### LIBRARY

Standard C Library (libc, -lc)

### SYNOPSIS

```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 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 ```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(``) functions conforms to X/Open Portability Guide Issue 4, Version 2 (``XPG4.2'') .

### HISTORY

The ualarm(``) function appeared in 4.3BSD.