Usage

time [OPTS] <CLI> [ARG]

 * bash 內置的 time 與 /usr/bin/time 是有不同 !

help

/usr/bin/time --help

Example

/usr/bin/time curl -s https://datahunter.org -o /dev/null

0.07user 0.00system 0:02.67elapsed 3%CPU (0avgtext+0avgdata 13832maxresident)k
0inputs+0outputs (0major+1018minor)pagefaults 0swaps

time curl -s https://datahunter.org -o /dev/null

real    0m2.394s
user    0m0.083s
sys     0m0.008s

Opts

-a -o FILE            # "--append" information to the output file instead of overwriting it

-f FORMAT           #  當沒有設定時, 就會用 TIME environment variable

• %e   elapsed real time (wall clock) in seconds
• %S   system (kernel) time in seconds
• %U   user time in seconds
• %P   percent of CPU this job got
• ...