Grep on Michael’s Domain

Finding files with find

Mon, 24 Sep 2007 00:00:00 +0000

Finding files with the find command is actually more difficult than it should be. This finds and lists the largest files (more than 200 MB) on the whole file system:find / -type f -size +200000k -exec ls -lh {} \; | awk '{ print $9 ": " $5 }'The same, but simpler syntax:find / -size +200M -lsThis finds the most recently changed files under the current directory:find . -type f -printf '%TY-%Tm-%Td %TT %p\n' | sortAnd this command pipes the results of the find command into another command. First find looks for Quicktime movies (based on the file extension .mov) and then ffmpeg converts them into avi files.find . -name '*.mov' -exec sh -c 'ffmpeg -i "$0" -sameq "${0%%.mov}.avi"' {} \;This commands finds and lists all filenames that contain the string ‘bitcoin’:find . -name '*bitcoin*' -lsAnd this command finds Quicktime movies and deletes them:find . -name '*.mov' -exec sh -c 'rm "$0"' {} \;And this finds files that have been modified (created or updated) during the last 2 minutes:find . -cmin 2This finds crap which you copied over from a Macintosh and which you don’t need under Linux:find . -name '*.DS_Store' -type f -deleteSimilar story here:find . -name '._*' -type f -deleteWhen being in the root directory, this should find all files with the name ‘syncthing’:find . -name 'syncthing' -lsAnd this finds all files larger than 200MB in the /home directory:find /home -size +200M -lsFind recursively all files that end in .gz and count them:find . -name '*.gz' | wc -lFind recursively all files that do NOT end in .gz and count them:find . -not -name '*.gz' | wc -lWhen you want to search recursively through the content of text files, you need to use the grep command:grep -rnw '/path/to/target-directory' -e 'pattern'When you search for PDF files modified in October 2024:sudo find / -type f -name "*.pdf" -newermt "2024-10-01" ! -newermt "2024-11-01" 2>/dev/null

grep to search for file content or rpm -qa output

Fri, 25 May 2007 00:00:00 +0000

In order to search a specific directory (path_to_directory) and all its subdirectories (-r for recursive) for files that contain a specific text string, use the following command:grep -r "textstring" path_to_directoryAlso very useful is to pipe the output of another process into grep. E.g. you want to know whether a specific rpm package is installed on your system, but you don’t remember the exact name. Thus you cannot use the “rpm -q packagename”. In that cast you can ask rpm for all installed packages (rpm -qa) and then pipe this output to grep and let grep look for a substring from the packagename that you do remember:rpm -qa | grep substringE.g. when the package modutils-2.4.22-8 is installed you have to ask rpm:rpm -q modutils OR rpm -q modutils-2.4.22in order to get an answer. The request rpm -q modutils-2.4 would be: The package modutils-2.4 is not installed. Thus if you don’t know the exact name of the package, it is a safe bet to grep the rpm output for something you remember exactly.

Recursive grep

Thu, 05 Apr 2007 00:00:00 +0000

grep (case-insensitive, recursive) grep doesn’t offer any possibility to recursively descent down the directory tree. The following command searches e.g. just thru all the files in the current directory:grep bacteria *To make the search case-insensitive, one can use the i flag:grep -i bacteria *But if you want to do a recursive search you have to use a quite complicated construction of UNIX commands to achieve this goal:find ~/Mail -type f -exec grep 'bacteria' {} \; -printThis command searches recursively thru the Mail directory of the current user and prints all the lines that contain the word bacteria.