NAME
    sleep - suspend operation for a specified time

SYNOPSIS
    sleep([n])

TYPES
    n		non-negative real, defaults to 1

    return	integer or null value

DESCRIPTION
    This uses the C-library sleep (if n is integral) or usleep (for
    non-integral n) to suspend operation for n seconds.  If n is an
    integer and the sleep is stopped by an interruption, the number
    of seconds remaining is returned.

    One kind of use is to slow down output to permit easier reading of
    results, as in:

	> for (i = 0; i < 100; i++) {
		print sqrt(i);
		sleep(1/2);
	}

    The following illustrates what happens if ctrl-C is hit 5 seconds
    after the first command:

	> print sleep(20)

	[Abort level 1]
	15
	>

EXAMPLE
    > sleep(1/3);
    > sleep(20);

LIBRARY
    none

SEE ALSO
    none