sleep - block for some number of seconds
sleep EXPR
sleep
Causes the script to sleep for
EXPR seconds, or forever if no
EXPR. May be interrupted if the process receives a signal such as
SIGALRM. Returns the number of seconds actually slept. You probably cannot mix alarm() and sleep() calls, because sleep() is often implemented using alarm().
On some older systems, it may sleep up to a full second less than what you requested, depending on how it counts seconds. Most modern systems always sleep the full amount. They may appear to sleep longer than that, however, because your process might not be scheduled right away in a busy multitasking system.
For delays of finer granularity than one second, you may use Perl's
syscall() interface to access
setitimer(2) if your
system supports it, or else see select() above.
See also the
POSIX module's sigpause() function.
If rather than formatting bugs, you encounter substantive content errors in these documents, such as mistakes in the explanations or code, please use the perlbug utility included with the Perl distribution.