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blish_blash

12-31-2003 08:21 AM

why does if [ ${var:0:2}='AA' ] always return true

Hi and happy new year !
can someone tell me why does

if [ ${var:0:2}='AA' ]

always return true, and tell me how to change if to test the first two characters in variable var ?

Greetings,
Ron

Hko	12-31-2003 08:51 AM

Happy new year to you too.

That happens because you need to have spaces around the '='.
It's also better (at least in this case) to have double quotes around ${var:0:2}. Without the double quotes you'll get an error if "var" happens to be emtpy.

So, this works:

Code:

#!/bin/bash



var=$1



if [ "${var:0:2}" = "AA" ] ; then

    echo True

fi

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