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stringbashconsoletrim

bash truncate string Works on commandline but not in script

I am trying to cut off all occurrences of a character from the end of a string.

The test script I came up with is:

#!/bin/bash
Input="/tmp/blah/bloh/////////////"

Desired="/tmp/blah/bloh"

cut='/'

result=${Input%%+(${cut})}

echo "          Input: ${Input}"
echo "Expected result: ${Desired}"
echo "         Result: ${result}"
echo "---------------------------------------"
echo -n "        Outcome: "

[ "${Desired}" = "${result}" ] && echo "Success!" || echo "Fail!"

Running this script via bash /tmp/test.sh gives the following output:

          Input: /tmp/blah/bloh/////////////
Expected result: /tmp/blah/bloh
         Result: /tmp/blah/bloh/////////////
---------------------------------------
        Outcome: Fail!

However, if I copy and paste the entire thing in my console I get the expected result of /tmp/blah/blah

What is going on here?

Solution

  • +(${cut}) is an extended pattern, which bash does not recognize by default. You need to enable the extglob option first.

    $ shopt -s extglob
$ Input="/tmp/blah/bloh/////////////"
$ cut='/'
$ echo "${Input%%+(${cut})}"
/tmp/blah/bloh

    You probably have extglob enabled in your interactive shell via your .bashrc or .bash_profile configuration file, but neither file is used for the non-interactive shell started by your script.