sleep

Additional Notes

sleep pauses execution for a given amount of time, then exits. It is commonly used in loops, retry waits, and scripts that must pace their actions.

Sleep time can be a plain number (seconds) or a number with a unit suffix such as m for minutes or h for hours.

Syntax

sleep NUMBER[SUFFIX]...

Parameters

• NUMBER: How long to sleep; may be a decimal.
• SUFFIX: Unit for the number.

Time Suffixes

• s: Seconds (default when no suffix is given).
• m: Minutes.
• h: Hours.
• d: Days.

Multiple arguments are summed, so sleep 1m 30s sleeps 90 seconds.

Examples

sleep 5

Pause for five seconds.

sleep 0.5

Pause for half a second.

sleep 2h

Pause for two hours.

sleep 1m 30s

Pause for one and a half minutes.

while true; do
  check-status
  sleep 1
done

Run a check every second in a loop.

until curl -sf https://example.com; do
  sleep 5
done

Wait five seconds between retries until a host responds.

Practical Notes

• Decimals are allowed, such as sleep 0.2 for short pacing.
• Combine units by passing several arguments; they are added together.
• Useful for rate-limiting loops, retry backoff, and scripted waits.
• A Ctrl-c interrupts sleep immediately.