I have a program which spits out an output to stdout
like:
[OK] Something is ok
[OK] Something else is also ok
[FAIL] This does not look good
[FAIL] Neither does this
[OK] At least this is fine
To more easy spot the fails from the output I would like to mark the occurrences of the keyword FAIL
with red without discarding the other messages. It would be nice if I could also highlight the OK
keywords with green :).
Doing a pipe to egrep --color FAIL
will only show the lines where the FAIL
keyword is present.
Best Answer
Based on
manatwork
's brilliant little "or nothing" hack in the other question, I offer this, which adds the ability to get two highlight colors:That is, you run
grep
over the output twice, with a differentGREP_COLORS
environment variable each time.The '01;32' value means "bold green", and the other means "bold red". See the Wikipedia article on ANSI codes for more ideas.
Alas, this requires GNU grep version 2.5.3 or higher. Older versions of GNU grep supported a different coloring mechanism, but those versions have a bug that prevents you from using the feature in a pipeline more than once. BSD grep emulates the older GNU grep coloring mechanism, and it will work twice in a pipeline, but it yells about "empty sub-expression" due to the
manatwork
hack.You can remove the backslashes at the end of the first two lines to make it all a single line. I've just split it here for clarity and to play nice with the SE page format.