Bash – Remove a fixed prefix/suffix from a string in Bash

bash

In my bash script I have a string and its prefix/suffix. I need to remove the prefix/suffix from the original string.

For example, let's say I have the following values:

string="hello-world"
prefix="hell"
suffix="ld"

How do I get to the following result?

result="o-wor"

Best Solution

$ foo=${string#"$prefix"}
$ foo=${foo%"$suffix"}
$ echo "${foo}"
o-wor

This is documented in the Shell Parameter Expansion section of the manual:

${parameter#word}
${parameter##word}

The word is expanded to produce a pattern and matched according to the rules described below (see Pattern Matching). If the pattern matches the beginning of the expanded value of parameter, then the result of the expansion is the expanded value of parameter with the shortest matching pattern (the # case) or the longest matching pattern (the ## case) deleted. […]

${parameter%word}
${parameter%%word}

The word is expanded to produce a pattern and matched according to the rules described below (see Pattern Matching). If the pattern matches a trailing portion of the expanded value of parameter, then the result of the expansion is the value of parameter with the shortest matching pattern (the % case) or the longest matching pattern (the %% case) deleted. […]