How to find all files containing specific text on Linux

Do the following:

grep -rnw '/path/to/somewhere/' -e 'pattern'

• -r or -R is recursive,
• -n is line number, and
• -w stands for matching the whole word.
• -l (lower-case L) can be added to just give the file name of matching files.
• -e is the pattern used during the search

Along with these, --exclude, --include, --exclude-dir flags could be used for efficient searching:

grep --include=\*.{c,h} -rnw '/path/to/somewhere/' -e "pattern"
grep --exclude=\*.o -rnw '/path/to/somewhere/' -e "pattern"
grep --exclude-dir={dir1,dir2,*.dst} -rnw '/path/to/search/' -e "pattern"