How to convert string to integer in UNIX

Question

I have d1=\"11\" and d2=\"07\". I want to convert d1 and d2 to integers and perform d1-d2. How do I do this

Answer 1

Any of these will work from the shell command line. bc is probably your most straight forward solution though.

Using bc:

$ echo "$d1 - $d2" | bc

Using awk:

$ echo $d1 $d2 | awk '{print $1 - $2}'

Using perl:

$ perl -E "say $d1 - $d2"

Using Python:

$ python -c "print $d1 - $d2"

all return

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