Understanding UNIX `time` command output
Bizarrely, I couldn’t find any documentation as to the output from the UNIX (BASH shell version 3.2.57(1)-release , here) `time` command. I thought I had it, but I wanted to be sure, so I wrote a quick shell script to verify my understanding. A script that takes 1 minute, 5 seconds to run will have output that looks something like this: iMac:~ me$ cat time_test.sh #!/bin/bash sleep 65 echo " Done. " iMac:~ me$ time ./time_test.sh Done. real 1m5.016s user 0m0.003s sys 0m0.006s An hour, 2 minutes, and 8 seconds ( sleep 3728 ): real 62m8.083s user 0m0.003s sys 0m0.007s A script that completes in approximately 2 seconds ( sleep 2 ): real 0m2.014s user 0m0.003s sys 0m0.006s Mystery solved.