mjhjmtu

I am trying to grep for only for a range of numbers located inside parenthesis. My current grep will pull everything within the parenthesis but I just want anything from [0001-9999]. How can I fix my grep to do this?

I have tried a few different version of this (?<=()[0001-9999](?=)) but they don't return anything

$ cat /tmp/output
This is R3trans version 6.26 (release 745 - 24.03.17 - 20:17:03).
R3trans finished (0000).
R3trans finished (0001).
R3trans finished (9999).
05.03.2018 16:30:02
enserver, EnqueueServer, RED, Running, 2018 02 27 09:15:52, 151:14:10, 19069

Current output

$ cat /tmp/output | grep -Po '(?<=().*(?=))'
release 745 - 24.03.17 - 20:17:03
0000
0001
9999

Desired output

$ cat /tmp/output | grep -Po '(?<=().*(?=))'
0001
9999

Two approaches to reach the goal:

grep approach (with Perl support):

grep -Po '(K(?!0000)([0-9]4)(?=))' /tmp/output

GNU awk approach:

awk -v FPAT='\([0-9]4\)' '$1 n = substr($1,2,4); if (int(n) > 0) print n ' /tmp/output

The output:

0001
9999

Apparently you have numeric constrains. If this is the case, why not using a programming language? Example:

perl -nE '/((d4))/ and $1 > 0 and say $1'

This appears to work:

grep -Eo '[0-9]4' /path/to/file | grep -v '0000'

Less readable, but with only one grep:

grep -Eo '[0-9]3[1-9]|[0-9]2[1-9][0-9]|[0-9][1-9][0-9]2|[1-9][0-9]3' /path/to/file