Modify config file using bash script

Question

I'm writing a bash script to modify a config file which contains a bunch of key/value pairs. How can I read the key and find the value and possibly modify it?

Answer 1

A wild stab in the dark for modifying a single value:

sed -c -i "s/($TARGET_KEY *= *).*/1$REPLACEMENT_VALUE/" $CONFIG_FILE

assuming that the target key and replacement value don't contain any special regex characters, and that your key-value separator is "=". Note, the -c option is system dependent and you may need to omit it for sed to execute.

For other tips on how to do similar replacements (e.g., when the REPLACEMENT_VALUE has '/' characters in it), there are some great examples here.