Wrong bash script syntax

Question

I have a script part where I am checking if the file exist . I dont find where is my mistake because it jumps to else( file exists) and starts downloading that file. Part of code:

...
    if [ -f '$ins.img' ];
    then
        echo '$ins.img already exists'
    else
       wget http://$2/$ins/$ins.img
    fi
...

Variables don't expand in single quotes. – Etan Reisner Apr 08 '15 at 12:23 — Etan Reisner, Apr 08 '15 at 12:23
lol , i didnt know there is a difference – Dambre Apr 08 '15 at 12:28 — Dambre, Apr 08 '15 at 12:28

score 0 · Accepted Answer · answered Apr 08 '15 at 12:24

0

It's because you're using single quotes in your if. Variables are not filled in inside single quotes, so it will check for a file literally named $ins.img, which obviously doesn't exist.

The solution is easy, use double quotes.

answered Apr 08 '15 at 12:24

Bart van Heukelom

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Didnt know there is a difference of those. Thanks by the way :)) – Dambre Apr 08 '15 at 12:29

Wrong bash script syntax

1 Answers1