grep : how to color 2 keywords?

I know how to grep 2 keywords using 1 command, but I can only manage to color one of them in output . Here is my command:

grep 'keyword1' file.log | grep 'keyword2'

Only keyword2 is highlighted. How can I make keyword1 highlighted at the same time ?

Solution 1:

The grep command accepts a --color=always option, so you can use

grep 'keyword1' file.log --color=always | grep 'keyword2'

As gertvdijk points out, this command may be inefficient, but it will look for all lines that contain both keyword1 and keyword2. If you want to highlight them in different colors, you can use

grep 'keyword1' file.log --color=always | GREP_COLORS="mt=01;34" grep --color=always 'keyword2'

which will highlight keyword2 in blue. The mt part means that grep will highlight matching text using this CSI code, and 01;34 means "bold blue foreground on normal background".

Solution 2:

Try actual regular expressions, rather than piping to another instance of grep, e.g.:

grep -E "\<foo\>.*\<bar\>" file

This limits to matching lines in which this the keywords match in this order only, unfortunately. Anyway, the use of grep in your question is rather inefficient and you should avoid it. The answer of @DanielH is pretty much more straightforward for your case, probably.

For an 'or' matching of keywords, I use this regularly:

grep -E "(foo|bar)" file