Commands using grep (1,935)

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Share Your Commands


Check These Out

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

Gets the english pronunciation of a phrase
Sends a string to google tranlator, which converts it to English speech. It's possible to create a nice script to do the job for us, such as #!/bin'bash curl -A "Mozilla" "http://translate.google.com/translate_tts?tl=en&q=$1" > /tmp/speak.mp3 mplayer /tmp/speak.mp3

rename all images in folder with prefix of date and time from exif data
jhead is required

Renaming a file without overwiting an existing file name
Sometimes in a hurry you may move or copy a file using an already existent file name. If you aliased the cp and mv command with the -i option you are prompted for a confirmation before overwriting but if your aliases aren't there you will loose the target file! The -b option will force the mv command to check if the destination file already exists and if it is already there a backup copy with an ending ~ is created.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Print all open regular files sorted by the number of file handles open to each.
List all open files of all processes. . $ find /proc/*/fd Look through the /proc file descriptors . $ -xtype f list only symlinks to file . $ -printf "%l\n" print the symlink target . $ grep -P '^/(?!dev|proc|sys)' ignore files from /dev /proc or /sys . $ sort | uniq -c | sort -n count the results . Many processes will create and immediately delete temporary files. These can the filtered out by adding: $ ... | grep -v " (deleted)$" | ...

Alias TAIL for automatic smart output
Run the alias command, then issue $ps aux | tail and resize your terminal window (putty/console/hyperterm/xterm/etc) then issue the same command and you'll understand. $ ${LINES:-`tput lines 2>/dev/null||echo -n 12`} Insructs the shell that if LINES is not set or null to use the output from `tput lines` ( ncurses based terminal access ) to get the number of lines in your terminal. But furthermore, in case that doesn't work either, it will default to using the default of 80. The default for TAIL is to output the last 10 lines, this alias changes the default to output the last x lines instead, where x is the number of lines currently displayed on your terminal - 7. The -7 is there so that the top line displayed is the command you ran that used TAIL, ie the prompt. Depending on whether your PS1 and/or PROMPT_COMMAND output more than 1 line (mine is 3) you will want to increase from -2. So with my prompt being the following, I need -7, or - 5 if I only want to display the commandline at the top. ( http://www.askapache.com/linux/bash-power-prompt.html ) 275MB/748MB [7995:7993 - 0:186] 06:26:49 Thu Apr 08 [askapache@n1-backbone5:/dev/pts/0 +1] ~ $ In most shells the LINES variable is created automatically at login and updated when the terminal is resized (28 linux, 23/20 others for SIGWINCH) to contain the number of vertical lines that can fit in your terminal window. Because the alias doesn't hard-code the current LINES but relys on the $LINES variable, this is a dynamic alias that will always work on a tty device.

Pack up some files into a tarball on a remote server without writing to the local filesystem
I recently found myself with a filesystem I couldn't write to and a bunch of files I had to get the hell out of dodge, preferably not one at a time. This command makes it possible to pack a bunch of files into a single archive and write it to a remote server.

find both total size and number of files below any given svn directory
afaik, svn doesn't have a good, scriptable way of telling you these two basic pieces of information.

search office documents for credit card numbers and social security number SSN docx xlsx
# CC with SSN dash ( low false positive only match ###-##-#### not any 8digi number ) $ find . -iname "*.???x" -type f -exec unzip -p '{}' '*' \; | sed -e 's/]\{1,\}>/ /g; s/[^[:print:]]\{1,\}/ /g' | egrep "\b4[0-9]{12}(?:[0-9]{3})?\b|\b5[1-5][0-9]{14}\b|\b6011[0-9]{14}\b|\b3(?:0[0-5]\b|\b[68][0-9])[0-9]{11}\b|\b3[47][0-9]{13}\b|\b[0-9]{3}-[0-9]{2}-[0-9]{4}\b" $ rmccurdyDOTcom


Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for: