I'd like to use the time command in a bash script to calculate the elapsed time of the script and write that to a log file. I only need the real time, not the user and sys. Also need it in a decent format. e.g 00:00:00:00 (not like the standard output). I appreciate any advice.
A:
Archimedix
2010-09-10 11:01:19
Seems incorrect: Time in seconds: 46 (OK), Pretty format: 00:00:00:46 (incorrect). Using time command: real 0m46.018s user 0m7.630s sys 0m1.190s
Robertico
2010-09-10 11:19:49
Hm, I'm not quite sure what 00:00:00:00 is supposed to mean – I was guessing it meant [days]:[hours]:[minutes]:[seconds] ? That is what it shows, but you are free to adjust the code to calculate what you need.
Archimedix
2010-09-10 12:02:11
excuses for the typo.Supposed to be 00:00:00.0000 (milliseconds)[hours]:[minutes]:[seconds].[milliseconds]
Robertico
2010-09-10 12:23:03
A:
Not quite sure what you are asking, have you tried:
time yourscript | tail -n1 >log
Edit: ok, so you know how to get the times out and you just want to change the format. It would help if you described what format you want, but here are some things to try:
time -p script
This changes the output to one time per line in seconds with decimals. You only want the real time, not the other two so to get the number of seconds use:
time -p script | tail -n 3 | head -n 1
Amoss
2010-09-10 11:02:24
Yes, if that was unambiguous then I wouldn't pointed out that it needs clarification. Why not use two scripts, one that calls the other?
Amoss
2010-09-10 11:50:05
Because i've already 3 scripts. I saw an example like this: { time { # section code goes here} } 2> timing.logBut i only need the real time, not the user and sys. Also need it in a decent format. e.g 00:00:00:00 (not like the standard output).
Robertico
2010-09-10 11:58:15
ok, so you already know how to time a section, so that was just unnecessary confusion in your question. Is what you really want to know how to turn the time output into something easier to process, like just the number of seconds?
Amoss
2010-09-10 16:42:26
yes i'd like to know how to turn the time output into something easier to process.
Robertico
2010-09-11 05:46:15
+2
A:
From the man page for time: 1)There may be a shell built-in called time, avoid this by specifying /usr/bin/time 2)You can provide a format string and one of the format options is elapsed time - %E
/usr/bin/time -f'%E' $CMD
Example:
/usr/bin/time -f'%E' ls /tmp/mako/
res.py res.pyc
0:00.01
Martin Thomas
2010-09-10 15:44:37
That's why the command: time -f'%E' was not working, but /usr/bin/time -f'%E' works fine. Thx
Robertico
2010-09-10 16:10:29
A:
To use the Bash builtin time rather than /bin/time you can set this variable:
TIMEFORMAT='%3R'
which will output the real time that looks like this:
5.009
or
65.233
The number specifies the precision and can range from 0 to 3 (the default).
You can use:
TIMEFORMAT='%3lR'
to get output that looks like:
3m10.022s
The l (ell) gives a long format.
Dennis Williamson
2010-09-10 16:25:14