How to use square brackets in grep for MINGW64?

Question

Currently, I have a following regex. It should match a string that I am echoing:

echo "TBGFSGFI22800_D_REP_D_RISIKOEINHEIT" | grep -E 'TBGFSGFI\d\d\d\d\d[A-Za-z_]{1,100}' 

It works as expected in OsX on my Mac and in Notepad++, but in Bash for windows (MINGW64) I get an empty string. How can I use the grep with flags, or how should I rewrite the regex to match the pattern?

My grep version is 3.1. Bash: 4.4.23(1)

Thanks for help in advance!

Answer 1

You are using a POSIX ERE regex with the -E option, and that flavor does not support \d construct. You also need -o option to actually extract the matches.

Note you do not need to repeat \d five times, you can use a range quantifier, \d{5}.

You can use

echo "TBGFSGFI22800_D_REP_D_RISIKOEINHEIT" | grep -Po "TBGFSGFI\d{5}[A-Za-z_]{1,100}" 

Where

• -P means the regex is of a PCRE flavor
• -o extracts matches only
• TBGFSGFI\d{5}[A-Za-z_]{1,100} - a regex that matches TBGFSGFI, then any five digits and then 1-100 ASCII letters or _.