All commands (14,187)

  • Extremely useful to maintain backups if you're using Dropbox. This mirrors the entire directory structure and places symlinks in each to the original file. Instead of copying over the data again to the ~/Dropbox folder creating a symbolic link tree is much more sensible in terms of space usage. This has to be supplemented by another script that removes dead symlinks in the Dropbox folder which point to files that have been moved/removed. find -L ./ -type l -delete And then removing empty directories find ./ -type d -exec rmdir 2>/dev/null {} \; **Actually after some finding I found lndir which creates symbolic trees but it wasn't in the Arch repos so.. ;)


    0
    find /home/user/doc/ -type d -printf "mkdir -vp '/home/user/Dropbox%p'\n" -o -type f -printf "ln -vs '%p' '/home/user/Dropbox%p'\n" | sh
    jnash · 2009-03-29 09:25:12 23
  • Nice interface for an info page.


    1
    yelp info:foo
    renich · 2009-03-29 07:14:48 7
  • A great way of viewing some man page while using gnome.


    3
    yelp man:foo
    renich · 2009-03-29 07:13:44 8
  • This requires that your sudo not prompt for a password, as sftp cannot allocate the terminal necessary to ask.


    0
    sftp -s "sudo /usr/lib/sftp-server" user@host
    mrtheplague · 2009-03-29 07:02:58 6
  • Might be more useful if you were able to print it in Days HH:MM:SS format as: perl -e '@p=gmtime(234234);printf("%d Days %02d:%02d:%02ds\n",@p[7,2,1,0]);' But I'm not exactly sure how to replace the 234234 with the output of the countdown time. (Having some problems with nested quoting/command substitution). Help would be appreciated :)


    0
    watch --no-title -d -n 1 'echo `date -d "next Thursday" +%s` "-" `date +%s` | bc -l'
    jnash · 2009-03-29 06:53:09 9

  • 3
    dscacheutil -flushcache
    oarmas · 2009-03-29 06:17:32 5
  • Several times, I find myself hitting my up arrow, and changing the search term. Unfortunately, I find myself wasting too much time typing: grep kernel /var/log/messages Redirecting STDIN allows me to put the search term at the end so I less cursor movement to change what I'm searching for: < /var/log/messages grep kernel If you're using the emacs keyboard binding, then after you press your up arrow, press CTRL+w to erase the word. If this has already been submitted, I couldn't find it with the search utility.


    15
    < /path/to/file.txt grep foo
    atoponce · 2009-03-29 02:43:40 16
  • On Fedora clean the boot directory; erase older kernel


    1
    rpm -q kernel-2* | grep -v $(uname -r) | xargs yum erase -y
    Nick · 2009-03-28 21:41:15 11
  • Here is a command line to run on your server if you think your server is under attack. It prints our a list of open connections to your server and sorts them by amount. BSD Version: netstat -na |awk '{print $5}' |cut -d "." -f1,2,3,4 |sort |uniq -c |sort -nr Show Sample Output


    14
    netstat -ntu | awk '{print $5}' | cut -d: -f1 | sort | uniq -c | sort -n
    tiagofischer · 2009-03-28 21:02:26 73
  • This command is useful when you want to install the same packages on another fresh OS install for example. To do that, use: sudo dpkg --set-selections < LIST_FILE Show Sample Output


    11
    dpkg --get-selections > LIST_FILE
    o6291408 · 2009-03-28 17:45:29 12
  • Update a Mandriva Linux system with any pending updates. This command needs to be run with root privilege. Using the "--force" option answers "yes" to any interactive prompts thus allowing the updates to be left unattended to completion. NB if there is an update for glibc and/or a new kernel then the system would need to be rebooted for these to take effect. A prerequisite for running "urpmi --auto-update" is to have correctly defined urpmi media sources (which can be done by visiting http://easyurpmi.zarb.org/). If there are no new updates the the message "Packages are up to date" is shown. Show Sample Output


    0
    urpmi --auto-update --force # apply all pending updates (Mandriva Linux)
    mpb · 2009-03-28 14:59:26 8
  • I find this terribly useful for grepping through a file, looking for just a block of text. There's "grep -A # pattern file.txt" to see a specific number of lines following your pattern, but what if you want to see the whole block? Say, the output of "dmidecode" (as root): dmidecode | awk '/Battery/,/^$/' Will show me everything following the battery block up to the next block of text. Again, I find this extremely useful when I want to see whole blocks of text based on a pattern, and I don't care to see the rest of the data in output. This could be used against the '/etc/securetty/user' file on Unix to find the block of a specific user. It could be used against VirtualHosts or Directories on Apache to find specific definitions. The scenarios go on for any text formatted in a block fashion. Very handy.


    94
    awk '/start_pattern/,/stop_pattern/' file.txt
    atoponce · 2009-03-28 14:28:59 26
  • Packages: gmailfs fuse-utils libfuse2 gvfs-fuse Config files: /etc/gmailfs/gmailfs.conf; ~/.gmailfs.conf (make a copy from the another one) Unmount: fusermount -u /mount/path/ /etc/fstab (Optional): none /mount/path/ gmailfs noauto,user[,username=USERNAME,password=PASSWORD,fsname=VOLUME] 0 0 NOTES: - The options between [] are optional since they already setuped on the config files. - The '-p' flag shows a prompt for the password entry. - It's necessary to add the user to the 'fuse' group. You can do that with: sudo chgrp fuse /dev/fuse and sudo usermod -a -G fuse USER - The volume name is not needed but highly recommended to avoid file corruption. Also choose a non-trivial name. - Google doesn't approve the use of Gmail account other than e-mail purposes. So, I recommend the creation of a new account for this.


    5
    mount.gmailfs none /mount/path/ [-o username=USERNAME[,password=PASSWORD][,fsname=VOLUME]] [-p]
    o6291408 · 2009-03-28 13:00:47 5
  • Perform a dns zone transfer (if is allowed on target dns server) and print result.


    0
    host -la domain.com
    servermanaged · 2009-03-28 12:15:16 5
  • See: "man pwgen" for full details. Some Linux distros may not have pwgen included in the base distribution so you maye have to install it (eg in Mandriva Linux: "urpmi pwgen"). Show Sample Output


    6
    pwgen
    mpb · 2009-03-28 11:43:21 5
  • To install a theme use: sudo firefox -install-global-theme /path/to/theme You can get the .xpi or .jar file from the versions history on the add-on/theme page. NOTE: may not work in your system (Debian-based is an example).


    17
    sudo firefox -install-global-extension /path/to/add-on
    o6291408 · 2009-03-28 11:11:12 9
  • Not so useful. Just a cool feature.


    7
    mplayer -vo aa <video file>
    o6291408 · 2009-03-28 10:01:56 9
  • The download content part. NOTE: the '-c' seems to not work very well and the download stuck at 99% sometimes. Just finish wget with no problem. Also, the download may restart after complete. You can also cancel. I don't know if it is a wget or Rapidshare glitch since I don't have problems with Megaupload, for example. UPDATE: as pointed by roebek the restart glitch can be solved by the "-t 1" option. Thanks a lot.


    6
    wget -c -t 1 --load-cookies ~/.cookies/rapidshare <URL>
    o6291408 · 2009-03-28 09:13:35 5
  • In order to do that, first you need to save a cookie file with your account info. These commands do it (maybe you need to create the '.cookies' dir before). Also, you need to check the "Direct downloads" option on the Premium Zone >> Settings tab. You need to do this once (as long you maintain the file or your Rapidshare Premium account).


    4
    wget --save-cookies ~/.cookies/rapidshare --post-data "login=USERNAME&password=PASSWORD" -O - https://ssl.rapidshare.com/cgi-bin/premiumzone.cgi > /dev/null
    o6291408 · 2009-03-28 09:12:02 7
  • A great password generation tool. http://www.adel.nursat.kz/apg/ Show Sample Output


    3
    apg -a 0 -n 10
    renich · 2009-03-28 08:52:59 8
  • Within vi allow to empty a text file in one shot


    3
    :1,$d
    acirulli · 2009-03-28 02:28:19 12
  • The vi key sequence !}command will send the file contents from the cursor to the next blank line as STDOUT to the command specified and replace that sequence of file lines with the output of the command. For example: sorting a block of data - !}sort The sequence !{command will do the same but "upwards" (from the current position towards the start of the file. Show Sample Output


    12
    !}sort
    mpb · 2009-03-28 00:18:39 11

  • -13
    chmod +x FILES
    colinpj · 2009-03-27 23:28:40 5

  • -4
    sudo chmod -R g=u-w,g+X *
    mudiarto · 2009-03-27 23:27:12 5
  • head by default displays first ten lines of its output. Use 'head -nXX' to display the XX largest files


    -4
    ls -Sl * | head
    colinpj · 2009-03-27 23:20:32 7
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New command with the last argument of the previous command.

Multi-thread any command
For instance: $ find . -type f -name '*.wav' -print0 |xargs -0 -P 3 -n 1 flac -V8 will encode all .wav files into FLAC in parallel. Explanation of xargs flags: -P [max-procs]: Max number of invocations to run at once. Set to 0 to run all at once [potentially dangerous re: excessive RAM usage]. -n [max-args]: Max number of arguments from the list to send to each invocation. -0: Stdin is a null-terminated list. I use xargs to build parallel-processing frameworks into my scripts like the one here: http://pastebin.com/1GvcifYa

count the number of specific characters in a file or text stream
In this example, the command will recursively find files (-type f) under /some/path, where the path ends in .mp3, case insensitive (-iregex). It will then output a single line of output (-print0), with results terminated by a the null character (octal 000). Suitable for piping to xargs -0. This type of output avoids issues with garbage in paths, like unclosed quotes. The tr command then strips away everything but the null chars, finally piping to wc -c, to get a character count. I have found this very useful, to verify one is getting the right number of before you actually process the results through xargs or similar. Yes, one can issue the find without the -print0 and use wc -l, however if you want to be 1000% sure your find command is giving you the expected number of results, this is a simple way to check. The approach can be made in to a function and then included in .bashrc or similar. e.g. $ count_chars() { tr -d -c "$1" | wc -c; } In this form it provides a versatile character counter of text streams :)

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Fix "broken" ID3 tags in the current directory and subdirectories
Some MP3s come with tags that don't work with all players. Also, some good tag editors like, EasyTAG output tags that don't work with all players. For example, EasyTAG saves the genre as a numeric field, which is not used correctly in Sansa MP3 players. This command corrects the ID3 tags in MP3 files using mid3iconv, which comes with mutagen. To install Mutagen on Fedora use "yum install python-mutagen"

Factory reset your harddrive. (BE CAREFUL!)

add a backup (or any other) suffix to a file
Very helpful when you've got complex filenames and needs to change just some small parts of it. Renaming a file called "i-made-a-small-typo-right-here" to "i-made-a-big-typo-right-here": $ mv -vi i-made-a-{small,big}-typo-right-here You could also copy multiple files, edit, remove, process, etc.

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"

Go to parent directory of filename edited in last command

Convert JSON to YAML (unicode safe)
If you tried the other Python version of Convert JSON to YAML and you end up with lines that has "!!python/unicode", this version of the command is for you.


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