Not quite - that is run before your prompt is displayed. $ PROMPT_COMMAND='time=$(date +%T)' $ echo $time;date +%T 12:19:07 12:20:19 Thus it will show

Not quite - that is run before your prompt is displayed. $ PROMPT_COMMAND='time=$(date +%T)' $ echo $time;date +%T 12:19:07 12:20:19 Thus it will show the time after your last command returned rather than the current time.