Find in files, Linux

Question

Say I want to find all files that mention "Jonathan Appleseed" in a Linux system.

I see examples using grep, but I can't quite grep yet how to search (all directories from HERE). So I want to look in everything below /var/, for example

Answer 1

haha. It will take hours :> in any case .... grep -RE 'Jonathan Appleseed' R is for recursive, and E for case sensitive

Answer 2

If your grep doesn't have the -R option,

find /var -type f -print | xargs egrep 'Jonathan Appleseed'

will generally do what you're asking.

Answer 3

word = word that you want to search, if you want to search a phrase enclose between two single quotes

grep -iR <word> 

or

 find -name "*.xml" | xargs grep -iR <word>

combining find with grep allow you to make more accurate search combining grep content search with find file search, this is the avalaible option for find :

-name = search file for name (can contain wildcard char)
-iname = same, as name but case insensitive
-atime n = true, if file was accessed n days ago
-amin n = true, if file was accessed n minutes ago
-mtime n = true, if file contents were changed n days ago
-mmin n = true, if file content were changed n minutes ago
-ctime n = true, if file attributes were changed n days ago
-cmin n = true, if file attributes were changed n minutes ago
-regex expression = select files which match the regular expression
-iregex expression = same as above but case insensitive
-empty = select files and directories which are empty
-type filetype = Select file by Linux file types
-user username = Select files owned by the given user
-group groupname = Select files owned by the given group

For Search "Jonathan Appleseed" in /var dir under linux, i do something like this :

find /var | xargs grep -iR 'Jonathan Appleseed'

for search .txt file that contain term "Jonathan Appleseed", you cold do this :

find /var -iname "*.txt" | xargs grep -iR 'Jonathan Appleseed'

Answer 4

I want to find all files that mention "Jonathan Appleseed" in a Linux system.

You're looking for:

grep -l -r "Jonathan Appleseed" /

If you want to run a command on all matching files, I would suggest:

grep -l -z -r "Jonathan Appleseed" / | xargs -0 <your command here>

Note that -l means show only the filename (not matching text), -r means recursive, and -z (if you choose to use it) means the file names are null ("\0") terminated rather than terminated with a carriage return. This means xargs can handle filenames with spaces, tabs, and carriage returns in the name more readily.

I also am passing / to indicate that grep should start at the root of the filesystem ("all files... in a Linux system.")