Note that MadeInGermany's suggestion only works if there are only two fields on lines that start with SITES. It will replace the 2nd and any following fields the way it is currently written.

I will assume you're using bash as your shell (since cmd &> tmp runs cmd in the background and creates an empty file named tmp on most other shells).

And, I'll assume you're using GNU sed (since the -i option is one of the GNU extensions to sed). I'm not a fan of the -i option to sed (especially when a backup file option-argument is not supplied). But, I think you'll get a syntax error for a mismatched closing parenthesis on the command you showed us.

Assuming you wanted to use $site as an option-argument to the -i option, you might try:

Code:

sed --posix -i $site '/s/\("$site"'[[:space:]]+\)[^[:space:]]+/\1'"${mx}/" $FILENAME

This is untested, and I don't have a GNU sed available to test it. I think you'll need the --posix to get the RE and replacement processing in the substitute command to work correctly and I don't think that will disable the -i option, but the man page doesn't give nearly enough information for me to determine that.

On most systems sed will be faster than awk for small jobs because it is smaller and takes less time to exec. And, if you're running it thousands of time, the difference may matter. You'll have to run some performance tests to see which is faster on your configuration.

Note that this sed command will leave backup files laying around whether or not the command was successful and may leave the source file in an undefined state if an error was encountered (but you'll be able to manually restore it from the backup file) while your awk script with the mv command will get rid of tmp if the command completes successfully and leave the source file unchanged if it failed.