All commands

All commands (14,187)

sorted by

Optimal way of deleting huge numbers of files

Using xargs is better than: find /path/to/dir -type f -exec rm \-f {} \; as the -exec switch uses a separate process for each remove. xargs splits the streamed files into more managable subsets so less processes are required.
This is sample output - yours may be different.
12

find /path/to/dir -type f -print0 | xargs -0 rm

root · 2009-01-26 11:30:47 62
Display PHP files that directly instantiate a given class

This greps all PHP files for a given classname and displays both the file and the usage. Show Sample Output
This is sample output - yours may be different.
```
tao/tests/filter/TestUrl.php:        $this->objFilter = new filter_Url();
tao/classes/local/view/Photos.php:        $objFilter  = new filter_Url();
```
1

find . -name "*.php" -exec grep \-H "new filter_" {} \;

root · 2009-01-26 10:43:09 73
Run the last command as root

Useful when you forget to use sudo for a command. "!!" grabs the last run command.
This is sample output - yours may be different.
1219

sudo !!

root · 2009-01-26 10:26:48 250
Creates a customized search command

Creates a command alias ('cr' in the above example) that searches the contents of files matching a set of file extensions (C & C++ source-code in the above example) recursively within the current directory. Search configured to be in colour, ignore-case, show line numbers and show 4 lines of context. Put in shell initialisation file of your choice. Trivially easy to use, e.g: cr sha1_init Show Sample Output
This is sample output - yours may be different.
```
./openssl/signatures.c-600-xmlSecOpenSSLDsaSha1EvpInit(EVP_MD_CTX *ctx)
./openssl/signatures.c-601-{
./openssl/signatures.c:602:    return SHA1_Init(ctx->md_data);
./openssl/signatures.c-603-}
./openssl/signatures.c-604-
--
./openssl/signatures.c-706-    NULL,
./openssl/signatures.c-707-#else /* XMLSEC_OPENSSL_096 */
./openssl/signatures.c:708:    SHA1_Init,
./openssl/signatures.c-709-    SHA1_Update,
./openssl/signatures.c-710-    SHA1_Final,
```
0

alias cr='find . 2>/dev/null -regex '\''.*\.$c\|cpp\|pc\|h\|hpp\|cc$$'\'' | xargs grep --color=always -ni -C2'

chrisdrew · 2009-01-26 08:54:25 56
Outputs a sorted list of disk usage to a text file

Recursively searches current directory and outputs sorted list of each directory's disk usage to a text file. Show Sample Output
This is sample output - yours may be different.
```
712     .
328     ./test
176     ./lib
144     ./doc
100     ./test/data
96      ./lib/rake
64      ./doc/release_notes
```
6

du | sort -gr > file_sizes

chrisdrew · 2009-01-26 01:12:54 62
Watch how fast the files in a drive are being deleted

This can be useful when a large remove operation is taking place.
This is sample output - yours may be different.
6

watch "df | grep /path/to/drive"

root · 2009-01-25 21:16:41 674
Execute a command at a given time

This is an alternative to cron which allows a one-off task to be scheduled for a certain time.
This is sample output - yours may be different.
266

echo "ls -l" | at midnight

root · 2009-01-25 21:07:42 85
Analyse an Apache access log for the most common IP addresses

This uses awk to grab the IP address from each request and then sorts and summarises the top 10.
This is sample output - yours may be different.
22

tail -10000 access_log | awk '{print $1}' | sort | uniq -c | sort -n | tail

root · 2009-01-25 21:01:52 47
Add SVN keywords property to all PHP and Javascript files
This is sample output - yours may be different.
3

find . $ -name "*.php" -o -name "*.js" $ -exec svn propset svn:keywords Id {} \;

root · 2009-01-24 00:54:35 63
Count files beneath current directory (including subfolders)
This is sample output - yours may be different.
18

find . -type f | wc -l

root · 2009-01-23 17:19:32 74

Display the top ten running processes - sorted by memory usage

ps returns all running processes which are then sorted by the 4th field in numerical order and the top 10 are sent to STDOUT. Show Sample Output

106

ps aux | sort -nk +4 | tail

root · 2009-01-23 17:12:33 294

Checks all MySQL tables

See http://dev.mysql.com/doc/refman/5.0/en/myisamchk.html for further details. You can also repair all tables by running: myisamchk -r *.MYI
This is sample output - yours may be different.
-2

myisamchk /path/to/mysql/files/*.MYI

root · 2009-01-22 10:20:00 133
‹ First < 566 567 568

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

Remove all mail in Postfix mail queue.

Start a terminal with three open tabs

If you launch gnome-terminal manually, you can start with three open tabs

ettercap..

There weren't any one liners for ettercap on this site... tisk tisk :-) (of course you'll have to plugin your own values for the variables..)

Convert seconds to [DD:][HH:]MM:SS

Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Automatic ssh Session Logger

A wrapper around ssh to automatically provide logging and session handling. This function runs ssh, which runs screen, which runs script. . The logs and the screen session are stored on the server. This means you can leave a session running and re-attach to it later, or from another machine. . . Requirements: * Log sessions on a remote server * Transparent - nothing extra to type * No installation - nothing to copy to the server beforehand . Features: * Function wrapper delegating to ssh - so nothing to remember - uses .ssh/config as expected - passes your command line option to ssh * Self-contained: no scripts to install on the server * Uses screen(1), so is: - detachable - re-attachable - shareable * Records session using script(1) * Configurable log file location, which may contain variables or whitespace L="$HOME" # local variable L="\$HOME" # server variable L="some space" . Limitations: * Log dir/file may not contain '~' (which would require eval on the server) . . The sessions are named by the local user connecting to the server. Therefore if you detach and re-run the same command you will reconnect to your original session. If you want to connect/share another's session simply run: $ USER=bob ssh root@server . The command above is stripped down to an absolute minimum. A fully expanded and annotated version is available as a Gist (git pastebin): https://gist.github.com/flatcap/3c42326abeb1197ee714 . If you want to add timing info to script, change the command to: $ ssh(){ L="\$HOME/logs/$(date +%F_%H:%M)-$USER";/usr/bin/ssh -t "$@" "mkdir -p \"${L%/*}\";screen -xRRS $USER script --timing=\"$L-timing\" -f \"$L\"";}

Show a script or config file without comments or blank lines

Make vim open in tabs by default (save to .profile)

I always add this to my .profile rc so I can do things like: "vim *.c" and the files are opened in tabs.

Convert seconds to [DD:][HH:]MM:SS

List all bash shortcuts

This command shows the various shortcuts that can be use in bash, including Ctrl+L, Ctrl+R, etc... You can translate "\C-y" to Ctrl+y, for example.

Shorten any Url using bit.ly API, using your API Key which enables you to Track Clicks

Shorten any Url using bit.ly API, using your API Key which enables you to Track Clicks I have it as a Function in my .bash_aliases [code] shorten () { longUrl=$1; curl "http://api.bit.ly/shorten?version=2.0.1&longUrl=LONG_URL_YOU_WANT_SHORTENED&login=rungss&apiKey=" } [/code] Here is an Output showing the Function Detail.. [konsole] bijay@bijay:$ type shorten shorten is a function shorten () { longUrl=$1; curl "http://api.bit.ly/shorten?version=2.0.1&longUrl=$longUrl&login=rungss&apiKey=R_48d7e0b40835b09e3861bd455f7abec7" } [/konsole]

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:

» all commands
» commands with 3 up-votes (commandlinefu3)
» commands with 10 up-votes (commandlinefu10)

All commands (14,187) the last day the last week the last month all time sorted by date votes

What's this?

Check These Out

Stay in the loop…

All commands (14,187)

sorted by