File: coreutils.info,  Node: sleep invocation,  Up: Delaying

25.1 ‘sleep’: Delay for a specified time
========================================

‘sleep’ pauses for an amount of time specified by the sum of the values
of the command line arguments.  Synopsis:

     sleep NUMBER[smhd]...

   Each argument is a non-negative number followed by an optional unit;
the default is seconds.  The units are:

‘s’
     seconds
‘m’
     minutes
‘h’
     hours
‘d’
     days

   Although portable POSIX scripts must give ‘sleep’ a single
non-negative integer argument without a suffix, GNU ‘sleep’ also accepts
two or more arguments, unit suffixes, and floating-point numbers in
either the current or the C locale.  *Note Floating point::.

   For instance, the following could be used to ‘sleep’ for 1 second,
234 milli-, 567 micro- and 890 nanoseconds:

     sleep 1234e-3 567.89e-6

   Also one could sleep indefinitely like:

     sleep inf

   The only options are ‘--help’ and ‘--version’.  *Note Common
options::.

   Due to shell aliases and built-in ‘sleep’ functions, using an
unadorned ‘sleep’ interactively or in a script may get you different
functionality than that described here.  Invoke it via ‘env’ (i.e., ‘env
sleep ...’) to avoid interference from the shell.

   An exit status of zero indicates success, and a nonzero value
indicates failure.