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Terminal - All commands - 11,620 results
for file in `find . -type f`; do cat $file; done | wc -l
echo -n 'text to be encrypted' | openssl md5
2009-03-18 00:11:46
User: Zenexer
Functions: echo
17

Thanks to OpenSSL, you can quickly and easily generate MD5 hashes for your passwords.

Alternative (thanks to linuxrawkstar and atoponce):

echo -n 'text to be encrypted' | md5sum -

Note that the above method does not utlise OpenSSL.

top
2009-03-18 00:03:42
User: Zenexer
Functions: top
-5

A simple but effective replacement for ps aux. I used to waste my time running ps over and over; top is the way to go. It also allows complex sorting options. Press q to exit "nicely" (Ctrl + C is always an option, of course). Note that the list updates each second, resorting in the process; if you're trying to grab a specific PID, you might be better off with ps.

htop

Alternatively, htop is available, though it may not come pre-installed. htop is slightly more interactive than top and includes color coding, visuals, and a nice interface for selecting and then killing processes. (Thanks to bwoodacre for this great tool.)

^Z $bg $disown
2009-03-17 21:52:52
User: fall0ut
47

You're running a script, command, whatever.. You don't expect it to take long, now 5pm has rolled around and you're ready to go home... Wait, it's still running... You forgot to nohup it before running it... Suspend it, send it to the background, then disown it... The ouput wont go anywhere, but at least the command will still run...

sed ':a;N;$!ba;s/\n/ /g'
2009-03-17 20:54:04
User: cidiom
Functions: sed
Tags: Linux
0

Ever had a file with a list of numbers you wanted to add, use:

cat file | sed ':a;N;$!ba;s/\n/+/g' | bc
echo "test" | lp -d $PRINTER
2009-03-17 20:07:41
User: nauseaboy
Functions: echo lp
1

This will send a test print job to a networked printer.

vos listvldb | agrep LOCKED -d RWrite | grep RWrite: | awk -F: '{print $2}' | awk '{printf("%s ",$1)} END {printf("\n")}'
2009-03-17 19:55:39
User: mpb
Functions: awk grep
0

This command shows if there are any locked AFS volumes.

The output is a list of AFS volume IDs (or nothing if there are none locked).

mplayer tv:// -tv driver=v4l:width=352:height=288
2009-03-17 19:37:23
User: Robertof
9

Show the webcam output with mplayer.

startx > startx.log 2>&1
shopt -s nocaseglob
2009-03-17 17:51:42
User: josx
3

Change bash autocomplete case search to insensitive when pressing tab for completion.

shopt -s cdspell
ls -1 | rename 's/\ /_/'
2009-03-17 17:33:41
Functions: ls rename
4

Substitute spaces in filename with underscore, it work on the first space encountered.

<space>command
2009-03-17 16:25:29
User: eaZy
362

Prepending one or more spaces to your command won't be saved in history.

Useful for pr0n or passwords on the commandline.

Tested on BASH.

for i in `find /sys/devices/*/*/usb* -name level` ; do echo -n "$i: " ; cat $i ; done
rpm -qa --queryformat '%{installtime} \"%{vendor}\" %{name}-%{version}-%{release} %{installtime:date}\n' | grep "Thu 05 Mar"
2009-03-17 13:38:20
User: mpb
Functions: grep rpm
4

Find out which RPMs were installed on a particular date.

These would (naturally) include update RPMs.

This example shows searching for "Thu 05 Mar" (with grep).

Alternatively, pipe it to less so you can search inside less (with less's neat text highlighting of the search term):

rpm -qa --queryformat '%{installtime} \"%{vendor}\" %{name}-%{version}-%{release} %{installtime:date}\n' | less # (this example) search term: Thu 05 Mar

play $audio_file
2009-03-17 11:30:02
User: mpb
-3

"play" is part of "SoX"

SoX - Sound eXchange, the Swiss Army knife of audio manipulation.

For details, see: man sox

find -maxdepth 1 -type d -print0 | xargs -0 -I {} tar -cvzf {}.tar.gz {}
2009-03-17 11:12:53
User: piemme
Functions: find tar xargs
2

Create backup (.tar.gz) for all first-level directory from current dir.

lynx -accept_all_cookies -cmd_script=/your/keystroke-file
2009-03-17 00:38:36
User: Alanceil
25

This command will tell lynx to read keystrokes from the specified file - which can be used in a cronjob to auto-login on websites that give you points for logging in once a day *cough cough* (which is why I used -accept_all_cookies).

For creating your keystroke file, use:

lynx -cmd_log yourfile
:!cp % %-
2009-03-17 00:34:24
User: mpb
5

At the start of a vi session and *before* saving any changes use ":!cp % %-" to make a backup of the current file being edited.

example: vi /data/some/long/path/file

:!cp% %-

creates /data/some/long/path/file-

# indicates a comment in shell
2009-03-16 23:15:33
User: mpb
-4
#

Using the "#" in shell is surprisingly useful.

Some of the uses I found:

a) As a visible copy buffer in shell history (caveat: do not use for passwords :-)

b) To build complex commands until ready then hit the HOME, DEL, ENTER keys to run it

c) Placing reference data into shell history (search for tags with CTRL-R TAGNAME)

d) Putting aside a "work in progress" command to focus on another task (HOME # ENTER)

ctrl-z
2009-03-16 20:58:31
User: mallegonian
Tags: bash hotkey
11

Hold ctrl and press z to pause the current thread. Run

fg

to resume it.

convert -font -misc-fixed-*-*-*-*-*-*-*-*-*-*-*-* -fill black -draw "text 270,260 \" `cal` \"" testpic.jpg newtestpic.jpg
2009-03-16 16:09:58
User: dasmna
Tags: ImageMagick
15

Add calendar to desktop wallpaper , mess with the coordinates to place where you like

alias lvim="vim -c \"normal '0\""
cp ./* .[!.]* ..?* /path/to/dir
2009-03-16 13:27:36
User: ako
Functions: cp
0

./* is for copying files starting with -

.[!.]* is for copying hidden files and avoiding copying files from the parent directory.

..?* is for copying files starting with .. (avoids the directory ..)

/path/to/dir the path to the directory where the files should be copied

Can also be used as a script. Input argument is /path/to/dir

in tcsh, replace .[!.]* with .[^.]*

ffmpeg -vcodec copy -acodec copy -i orginalfile -ss 00:01:30 -t 0:0:20 newfile
2009-03-16 12:58:07
User: ako
19

With:

-vcodec, you choose what video codec the new file should be encoded with. Run ffmpeg -formats E to list all available video and audio encoders and file formats.

copy, you choose the video encoder that just copies the file.

-acodec, you choose what audio codec the new file should be encoded with.

copy, you choose the audio encoder that just copies the file.

-i originalfile, you provide the filename of the original file to ffmpeg

-ss 00:01:30, you choose the starting time on the original file in this case 1 min and 30 seconds into the film

-t 0:0:20, you choose the length of the new film

newfile, you choose the name of the file created.

Here is more information of how to use ffmpeg:

http://www.ffmpeg.org/ffmpeg-doc.html