I thought this might be easy but not so much
I want to color the output of a command based on delimeters, in my case
apt-show-versions -u
and want to color the packages' names based on the colon seperator, or on the word 'to'. It seems to run into wanting a parser not a filter.
using color xterm on Linux and PuTTY
Others have been interested in similar functionality, I suggest you check the tools (grc/grcat) mentioned there.
You might be able to get away with sed-magic, though. I'm not sure what you want to colour exactly, and neither do I know what the output of apt-show-versions looks like, but this colours everything preceding a colon and the word "to":
cat << EOF | sed -e "s/^[^:]*/\x1b[31m&\x1b[0m/g" | sed -e "s/to/\x1b[31m&\x1b[0m/g"
foo: 1 to 2
bar: 3 to 4
quux: 5 to 6
EOF
You can paste that into a terminal and see if it's what you're looking for. Essentially, it searches for occurences of regular expressions and surrounds it with ANSI colour codes:
s/X/Y&Y/g : replace X by surrounding with Y, in the entire input (g flag), or, quoting man sed:
s/regexp/replacement/
Attempt to match regexp against the pattern space. If success‐
ful, replace that portion matched with replacement. The
replacement may contain the special character & to refer to that
portion of the pattern space which matched, and the special
escapes \1 through \9 to refer to the corresponding matching
sub-expressions in the regexp.
^[^:]* : from beginning of line, match everything until you encounter a :
\x1b : Hex 27, an escape sequence (see here for more!)[31m : ANSI colour code for red[0m : ANSI colour code for "reset to normal output"If anything, this post taught me that sed captures matches in & ;-) Hope you gained some insight, too!
