I find myself using grep with

grep -i -n –color ‘string’ filename

most of the time. As you know, -i is for Ignore case, and -n for Number line, and –color colorizes the output.

An extremely useful thing to have is to set the environment variable

export GREP_OPTIONS="--color -i -n"

So I just need to type:

grep 'string' filename

and the output is already colorized, and has line number and case ignored.

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