The following article provides some useful tips on how to find all files within any specific directory or entire file-system containing any specific word or string.
The `-s` grep option will suppress error messages about nonexistent or unreadable files. The output shows filenames as well as prints the actual line containing requested string.
The above command omitted all sub-directories. To search recursively means to also traverse all sub-directories. The following command will search for a string `stretch` in all files within `/etc/` directory including all sub-directories:
#### Search for all files containing a specific word
The above `grep` command example lists all files containing string `stretch` . Meaning the lines with `stretches` , `stretched` etc. are also shown. Use grep's `-w` option to show only a specific word:
#### List only files names containing a specific text
The above commands may produce an unnecessary output. The next example will only show all file names containing string `stretch` within `/etc/` directory recursively:
All searches are by default case sensitive which means that any search for a string `stretch` will only show files containing the exact uppercase and lowercase match. By using grep's `-i` option the command will also list any lines containing `Stretch` , `STRETCH` , `StReTcH` etc., hence, to perform case-insensitive search.
#### Include or Exclude specific files names from search
Using `grep` command it is also possible to include only specific files as part of the search. For example we only would like to search for a specific text/string within configuration files with extension `.conf` . The next example will find all files with extension `.conf` within `/etc` directory containing string `bash` :
Same as with files grep can also exclude specific directories from the search. Use `--exclude-dir` option to exclude directory from search. The following search example will find all files containing string `stretch` within `/etc` directory and exclude `/etc/grub.d` from search:
#### Find all files not containing a specific string
The last example will use `-v` option to list all files NOT containing a specific keyword. For example the following search will list all files within `/etc/` directory which do not contain string `stretch` :
