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Terminal - All commands - 12,181 results
history -d
2009-04-27 20:19:09
User: sud0er
Tags: bash
28

If you're a moron like me, sometimes your fingers get away from you and you, for example, enter your password when you're already authenticated to ssh-agent, sudo, etc., and your password ends up in shell history. Here's how to get it out.

ssh -t user@some.domain.com /usr/bin/screen -xRR
2009-02-20 23:39:54
User: olifante
Functions: ssh
28

Long before tabbed terminals existed, people have been using Gnu screen to open many shells in a single text terminal. Combined with ssh, it gives you the ability to have many open shells with a single remote connection using the above options. If you detach with "Ctrl-a d" or if the ssh session is accidentally terminated, all processes running in your remote shells remain undisturbed, ready for you to reconnect. Other useful screen commands are "Ctrl-a c" (open new shell) and "Ctrl-a a" (alternate between shells). Read this quick reference for more screen commands: http://aperiodic.net/screen/quick_reference

mysqldump --add-drop-table --extended-insert --force --log-error=error.log -uUSER -pPASS OLD_DB_NAME | ssh -C user@newhost "mysql -uUSER -pPASS NEW_DB_NAME"
2009-02-17 17:57:53
User: Tscherno
Functions: ssh
28

Dumps a MySQL database over a compressed SSH tunnel and uses it as input to mysql - i think that is the fastest and best way to migrate a DB to a new server!

:TOhtml
2010-03-26 15:01:34
User: bartonski
27

While editing a source file in vim, or using vimdiff to compare two or more files, the ':TOhtml' command can be used to export each buffer as an html file, including syntax highlighting and vimdiff colorization. If you are in insert mode in vim, you will have to type

:TOhtml

This will open a new buffer filled with html, which you can then save.

pdftotext [file] - | grep 'YourPattern'
2010-02-14 21:42:35
User: drewk
Functions: grep
Tags: pipe grep pdf
27

PDF files are simultaneously wonderful and heinous. They are wonderful in being ubiquitous and mostly being cross platform. They are heinous in being very difficult to work with from the command line, search, grep, use only the text inside the PDF, or use outside of proprietary products.

xpdf is a wonderful set of PDF tools. It is on many linux distros and can be installed on OS X. While primarily an open PDF viewer for X, xpdf has the tool "pdftotext" that can extract formated or unformatted text from inside a PDF that has text. This text stream can then be further processed by grep or other tool. The '-' after the file name directs output to stdout rather than to a text file the same name as the PDF.

Make sure you use version 3.02 of pdftotext or later; earlier versions clipped lines.

The lines extracted from a PDF without the "-layout" option are very long. More paragraphs. Use just to test that a pattern exists in the file. With "-layout" the output resembles the lines, but it is not perfect.

xpdf is available open source at http://www.foolabs.com/xpdf/

for file in `ls *.pdf`; do convert -verbose -colorspace RGB -resize 800 -interlace none -density 300 -quality 80 $file `echo $file | sed 's/\.pdf$/\.jpg/'`; done
2009-02-15 23:27:43
User: brettalton
Functions: file sed
27

(relies on 'imagemagick')

This command will convert all .pdf files in a directory into a 800px (wide or height, whichever is smaller) image (with the aspect ratio kept) .jpg.

If the file is named 'example1.pdf' it will be named 'example1.jpg' when it is complete.

This is a VERY worthwhile command! People pay hundreds of dollars for this in the Windows world.

My .jpg files average between 150kB to 300kB, but your's may differ.

tidy -xml -i -m [file]
2009-02-05 21:22:33
User: scw
27

Generated XML files often are poorly formatted. Use this command to properly indent and normalize the file in-place.

python -m http.server
2010-12-17 12:52:45
User: Alanceil
Functions: python
26

In Python version 3, the module was merged into http.server. Gentlemen, change your aliases.

find / -type f -size +500M
echo $[RANDOM%X+1]
2010-08-07 02:43:46
Functions: echo
26

If X is 5, it will about a number between 1 and 5 inclusive.

This works in bash and zsh.

If you want between 0 and 4, remove the +1.

<ctrl+z> fg; notify_me
2010-05-20 16:16:43
User: recursiverse
26

If you want to be notified when a long-running command is finished, but you have already started it:

CTRL+Z

fg; echo "finished" | sendmail me@example.com

I use a script to post a tweet, which sends me a txt:

fg; echo "finished" | tweet
alias head='head -n $((${LINES:-`tput lines 2>/dev/null||echo -n 12`} - 2))'
26

Run the alias command, then issue

ps aux | head

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 deafault of 12 (-2 = 10).

The default for HEAD is to output the first 10 lines, this alias changes the default to output the first x lines instead, where x is the number of lines currently displayed on your terminal - 2. The -2 is there so that the top line displayed is the command you ran that used HEAD, 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-unix/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.

:w !sudo tee > /dev/null %
2010-03-24 20:04:26
User: idemal
Functions: tee
Tags: vim sudo tee
26

Write a file you edited in Vim but that you do not have the permissions to write to (unless you use sudo.) Same as #1204 but without the echo to stdout that I find annoying.

tar -cf - . | pv -s $(du -sb . | awk '{print $1}') | gzip > out.tgz
2009-12-18 17:09:08
User: opertinicy
Functions: awk du gzip tar
26

What happens here is we tell tar to create "-c" an archive of all files in current dir "." (recursively) and output the data to stdout "-f -". Next we specify the size "-s" to pv of all files in current dir. The "du -sb . | awk ?{print $1}?" returns number of bytes in current dir, and it gets fed as "-s" parameter to pv. Next we gzip the whole content and output the result to out.tgz file. This way "pv" knows how much data is still left to be processed and shows us that it will take yet another 4 mins 49 secs to finish.

Credit: Peteris Krumins http://www.catonmat.net/blog/unix-utilities-pipe-viewer/

ssh root@server.com 'tshark -f "port !22" -w -' | wireshark -k -i -
2009-12-17 23:03:24
User: markdrago
Functions: ssh
26

This captures traffic on a remote machine with tshark, sends the raw pcap data over the ssh link, and displays it in wireshark. Hitting ctrl+C will stop the capture and unfortunately close your wireshark window. This can be worked-around by passing -c # to tshark to only capture a certain # of packets, or redirecting the data through a named pipe rather than piping directly from ssh to wireshark. I recommend filtering as much as you can in the tshark command to conserve bandwidth. tshark can be replaced with tcpdump thusly:

ssh root@example.com tcpdump -w - 'port !22' | wireshark -k -i -
nl
date -d @1234567890
diff <(echo "$a") <(echo "$b")
2009-07-15 07:26:23
User: olorin
Functions: diff echo
26

You got some results in two variables within your shell script and would like to find the differences? Changes in process lists, reworked file contents, ... . No need to write to temporary files. You can use all the diff parameters you'll need. Maybe anything like $ grep "^>"

is helpful afterwards.

killall -STOP -m firefox
2009-05-18 20:02:44
Functions: killall
26

Continue with:

killall -CONT -m firefox

Suspends all Firefox Threads. Results in Zero CPU load.

Useful when having 100+ Tabs open and you temporarily need the power elsewhere.

Be careful - might produce RACE CONDITIONS or LOCKUPS in other processes or FF itself.

matching is case sensitive.

:mksession! <filename>
2009-02-26 05:03:07
User: neutral
Tags: vim
26

Creates a full snapshot of your current vim session, including tabs, open buffers, cursor positions, everything. Can be resumed with vim -S . Useful for those times when you HAVE to close vim, but you don't want to lose all your hard-opened buffers and windows. The ! will cause vim to overwrite the file if it already exists. It is not necessary, but useful if you frequently save to the same file (like session.vim or something).

svn log -q|grep "|"|awk "{print \$3}"|sort|uniq -c|sort -nr
2009-02-17 21:37:03
User: psytek
26

Use this command to find out a list of committers sorted by the frequency of commits.

<COMMAND> |:
2011-08-28 23:48:29
User: h3xx
25

This is shorter and actually much faster than >/dev/null (see sample output for timings)

Plus, it looks like a disappointed face emoticon.

diff <(lsusb) <(sleep 3s && lsusb)
2010-12-27 22:46:54
User: Juluan
Functions: diff sleep
25

I often use it to find recently added ou removed device, or using find in /dev, or anything similar.

Just run the command, plug the device, and wait to see him and only him

bind -x '"\C-l":ls -l'
2010-12-25 22:55:33
User: roalddevries
25

the -x option is for binding to a shell command

DISPLAY=:0.0 import -window root /tmp/shot.png
2010-10-28 12:00:00
User: depesz
25

Of course it requires import command, from imagemagick tools, but it's simpler to type, and imagemagick is usefull anyway.