sleep [OPTION]... NUMBER[SUFFIX]
The specification for sleep is as specified in the SUS but with the following differences.
The behaviors specified in this section are expected to disappear from a future version of the LSB; applications should only use the non-LSB-deprecated behaviors.
The operand to sleep in the SUS is the number of seconds to sleep for. As an extension, the number may be followed by s to keep seconds, m for minutes, h for hours or d for days.
displays help and exits.
outputs version information and exits.