How to save execution time of a script to variable while printing script's stdout to console?

Question

I would like to measure time spent on a script and save it to a variable. This is my current code:

time_spent=$(time ./script.sh)
...
echo $time_spent

Here is how it should work: The script output should go into the console immediately since the script may need user interaction. The time spent should be saved to a variable for later use.

Can this be done with time or should I use something else?

You could consider using the bash shell's built in SECONDS variable - see for example Time elapsed of a bash script (days/minutes/seconds) — steeldriver, Oct 28 '22 at 20:53
I would like to measure time with more precision, like the time command does — Qwerty-uiop, Oct 28 '22 at 20:56
You're probably not going to be able to use the output of bash's time. It's a shell built in and doesn't conform to normal redirection and capture of stdin and stdout. You should consider a wrapper script that grabs a timestamp from date before and after the script runs. — brunson, Oct 28 '22 at 21:05

score 1 · Accepted Answer · answered Oct 28 '22 at 21:12

1

/usr/bin/time rather than the time builtin can write the times to a file with the -o option.

$ /usr/bin/time -p -o times sleep 1
$ cat times
real 1.01
user 0.00
sys 0.00

See the man page for more info.

answered Oct 28 '22 at 21:12

brunson

179

How to save execution time of a script to variable while printing script's stdout to console?

1 Answers1