Question

I am trying to use the sed program to replace two lines of text in a config file using bash variables, the line replacement works however there is a extra space at the start of the line.

My commands are as follows:

replacement="computer_id = $server_ref"

(where $server_ref is a user entered variable)

and then:

sed "/computer_id/c \ ${replacement}" -i slapos.cfg

The other line being replaced uses just the same commands just changes a different variable in the config file.

The ouput of this change looks like

 computer_id = something

when it should be

computer_id = something

which results in crashing the program using the config as it is not excepting that space.

Answer 1

Might be better to do it like this:

sed -i "s/^\\(computer_id = \\).*/\\1${server_ref}/" slapos.cfg

The program which reads the configuration file isn’t very robust if extra whitespace crashed it.