sleep seconds
sleep continues running until the specified number of seconds has elapsed. sleep can delay execution of a program or produce periodic execution in conjunction with shell commands.
The seconds argument can be either a number of seconds, or a more general time description of the form nhnmns, with the nh, nm, and the s being optional.
sleep 20h10m
sleeps
for 20 hours and 10 minutes (or 72600 seconds).See Localization for more information.
POSIX.2, X/Open Portability Guide, UNIX systems.
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