sed to change a configuration file

Shell Programming and Scripting
1

Hi

I want to create a configuration file from a template one.

The only thing to change for now is the port number that I need to take from another file that has this format:

server:port

So I need to take the 2nd field.

server is passed in the script argument.

how to do that? I think of sed to search the file and get the port then find the line

Listen 80

to

Listen <port>

and then saves a new config file.

thanks for your help.

2

If you are sure it is always starting with the first character being the large 'L' and only 1 blank between "Listen" and "80" you can use this:

sed 's/^Listen 80/Listen \<Port\>/g' infile > httpd.conf.new

If you are unsure and want to get most possibilities taken into account (occurences of blanks and tabs etc.) you might use:

sed 's/^[<space>|<tab>]*Listen[<space>|<tab>]*80/Listen \<Port\>/g' infile > httpd.conf.new