How to grep a string in a directory and all its su

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How do I grep recursively? (24 answers)

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How to grep a string or a text in a directory and all its subdirectories'files in LINUX ??

Answer 1

grep -r -e string directory

-r is for recursive; -e is optional but its argument specifies the regex to search for. Interestingly, POSIX grep is not required to support -r (or -R), but I'm practically certain that System V grep did, so in practice they (almost) all do. Some versions of grep support -R as well as (or conceivably instead of) -r; AFAICT, it means the same thing.

Answer 2

If your grep supports -R, do:

grep -R 'string' dir/

If not, then use find:

find dir/ -type f -exec grep -H 'string' {} +