Extract one word after a specific word on the same line [duplicate]
How can I extract a word that comes after a specific word in Linux (csh)? More precisely, I have a file which has a single line which looks like this:
[some useless data] --pe_cnt 100 --rd_cnt 1000 [some more data]
I want to extract the number 100
which is after the --pe_cnt
word.
I cannot use sed as that works only if you want to extract an entire line. Maybe I can use awk?
Also, I have multiple files that have different values instead of 100
so I need something that extracts the value but doesn't depend on the value.
With awk
:
awk '{for(i=1;i<=NF;i++) if ($i=="--pe_cnt") print $(i+1)}' inputFile
Basically loop over each word of the line. When you find the first you are looking for, grab the next word and print it.
With grep
:
grep -oP "(?<=--pe_cnt )[^ ]+" inputFile
You can use sed. Just make a group of want you want to match and replace the whole line with the group:
sed -n 's/^.*pe_cnt\s\+\([0-9]\+\).*$/\1/p' file
If there is a single-space character between --pe_cnt
and 100
, you may be able to use lookahead and lookbehind assertions
grep -oP '(?<=--pe_cnt\s)\d+(?=\s+--rd_cnt)'