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0 pointsvacri8y ago0 comments

There is also the inbuilt variable $SECONDS, which seconds since the instance of bash was started. Makes it really easy to do 'time elapsed' at the end of a bash script.

    $ echo $SECONDS
    83783
    $ echo $SECONDS
    83784
    $ echo $SECONDS
    83787

0 comments

monsieurbanana8y ago

That's nifty.

    $ echo "$SECONDS / 60 / 60" | bc
    362.38500000000000000000

1024core8y ago

"bc", without the "-l" option, will give you integers only. So the response of the command above will be "362", and not "362.38500000000000000000"

mikegerwitz8y ago

echo "$(( SECONDS / 60 / 60 ))"

vram228y ago

echo "scale=2; $SECONDS / 60 / 60" | bc

# will give 2 digits after the decimal point, instead of bc -l which gives more digits of precision after the decimal point, than we may usually want for this particular calculation.

lozf8y ago

Recently I needed results that included nothing after the decimal point, so resorted to awk to do the math:

   awk "BEGIN { print int($SECONDS /60 /60)}"

1 more reply

otherflavors8y ago

printf "%s 60 60 *2k/p" "$SECONDS" | dc

alexanderdmitri8y ago

Yeah, SECONDS is great. I just discovered this a few days ago to get a general idea of execution time for each process a script handles:

# At top of script

SECONDS = 0

# script commands

...

# At bottom of script

duration=$SECONDS

echo "$(($duration / 60)) minutes and $(($duration % 60)) seconds elapsed."

samueloph8y ago

I prefer to use time when i want to know how much time some script took:

$ time sleep 2

real 0m2.003s

user 0m0.002s

sys 0m0.001s

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