how to remove comments from a bash script

Question

I'm trying to make a script that is getting a script file as a param. It should remove comments from the file and pipe it to another script. (with no temp file if possible)

at the beginning I was thinkig of doing this

cut -d"#" -f1 $1 | ./script_name

but it also clears a part of lines which aren't comments, because there are a few commands which uses # in them (counting string chars for example).

is there a way of doing it without a temp file?

Answer 1

You can use inline sed with better regex:

sed -i.bak '/^[[:blank:]]*#/d' "$1"

• ^[[:blank:]]*# will match # only if is preceded by optional spaces at each line

• -i.bak option will inline edit the input file with .bak as the extension of the backup file in case something goes wrong.

  sed -i.bak '/^[[:blank:]]*#/d' /etc/folder/config.rb a new file will be produced as /etc/folder/config.rb.bak with the comments removed, would be nice if emppty lines could be truncated.