Commands tagged Linux (250)

  • Requires installed command line PHP. Also, try at different dimensions of terminal window


    1
    php -r 'function a(){$i=10;while($i--)echo str_repeat(" ",rand(1,79))."*".PHP_EOL;}$i=99;while($i--){a();echo str_repeat(" ",34)."Happy New Year 2011".PHP_EOL;a();usleep(200000);}'
    galymzhan · 2011-04-21 05:08:56 0
  • Will rot 13 whatever parameter follows 'rot13', whether it is a string or a file. Additionally, it will rot 5 each digit in a number


    -5
    function rot13 { if [ -r $1 ]; then cat $1 | tr '[N-ZA-Mn-za-m5-90-4]' '[A-Za-z0-9]'; else echo $* | tr '[N-ZA-Mn-za-m5-90-4]' '[A-Za-z0-9]'; fi }
    twjolson · 2011-03-18 09:59:41 0

  • 10
    alias rot13="tr a-zA-Z n-za-mN-ZA-M"
    mathias · 2011-03-17 11:21:19 0
  • Note the double space: "...^ii␣␣linux-image-2..." Like 5813, but fixes two bugs: [1]This leaves the meta-packages 'linux-headers-generic' and 'linux-image-generic' alone so that automatic upgrades work correctly in the future. [2]Kernels newer than the currently running one are left alone (this can happen if you didn't reboot after installing a new kernel). I'm bummed that this took 228 characters. I'd like to see a simpler version. Show Sample Output


    7
    aptitude remove $(dpkg -l|awk '/^ii linux-image-2/{print $2}'|sed 's/linux-image-//'|awk -v v=`uname -r` 'v>$0'|sed 's/-generic//'|awk '{printf("linux-headers-%s\nlinux-headers-%s-generic\nlinux-image-%s-generic\n",$0,$0,$0)}')
    __ · 2010-12-11 11:38:15 3
  • Loop is needed if you have more then one card. Show Sample Output


    4
    for I in `/sbin/lspci |awk '/VGA/{print $1}'`;do /sbin/lspci -v -s $I;done
    houghi · 2010-10-26 19:02:26 0
  • probably only works if you have one graphics card. used this: http://www.cyberciti.biz/faq/howto-find-linux-vga-video-card-ram/ as reference can be expanded, for example: lspci -v -s `lspci | awk '/VGA/{print $1}'` | sed -n '/Memory.*, prefetchable/s/.*\[size=\([^]]\+\)\]/\1/p' will just get the amount of prefetchable memory compare to: lshw -C display which does not give the size (it does give byte ranges and you could calculate the size from that, but that's a pain) Also uses a command which is not standard on linux; wheras lspci is a core utility provided by most systems Show Sample Output


    1
    lspci -v -s `lspci | awk '/VGA/{print $1}'`
    infinull · 2010-10-26 17:45:14 0
  • Listens for events in the directory. Each created file is displayed on stdout. Then each fileline is read by the loop and a command is run. This can be used to force permissions in a directory, as an alternative for umask. More details: http://en.positon.org/post/A-solution-to-the-umask-problem%3A-inotify-to-force-permissions


    6
    inotifywait -mrq -e CREATE --format %w%f /path/to/dir | while read FILE; do chmod g=u "$FILE"; done
    dooblem · 2010-10-21 23:36:02 0
  • The command was too long for the command box, so here it is: echo $(( `wget -qO - http://i18n.counter.li.org/ | grep 'users registered' | sed 's/.*\<font size=7\>//g' | tr '\>' ' ' | sed 's/<br.*//g' | tr ' ' '\0'` + `curl --silent http://www.dudalibre.com/gnulinuxcounter?lang=en | grep users | head -2 | tail -1 | sed 's/.*<strong>//g' | sed 's/<\/strong>.*//g'` )) This took me about an hour to do. It uses wget and curl because, dudalibre.com blocks wget, and wget worked nicely for me. Show Sample Output


    -1
    Check the Description below.
    hunterm · 2010-10-07 04:22:32 0

  • -1
    wget -qO - http://i18n.counter.li.org/ | grep 'users registered' | sed 's/.*\<font size=7\>//g' | tr '\>' ' ' | sed 's/<br.*//g' | tr ' ' '\0'
    hunterm · 2010-10-07 03:19:17 0
  • look at /boot/grub/menu.lst for somethig like: ## additional options to use with the default boot option, but not with the ## alternatives ## e.g. defoptions=vga=791 resume=/dev/hda5 ## defoptions=vga=795 # defoptions=vga=873 ## altoption boot targets option ## multiple altoptions lines are allowed ## e.g. altoptions=(extra menu suffix) extra boot options ## altoptions=(recovery) single # altoptions=(verbose mode) vga=775 debug # altoptions=(console mode) vga=ask # altoptions=(graphic mode) quiet splash # altoptions=(recovery mode) single vga=(decimal value) is framebuffer mode Show Sample Output


    4
    sudo hwinfo --framebuffer
    hute37 · 2010-10-03 14:45:02 0
  • I use this command in my Conky script to display the number of messages in my Gmail inbox and to list the from: and subject: fields. Show Sample Output


    -3
    wget -O - 'https://USERNAMEHERE:PASSWORDHERE@mail.google.com/mail/feed/atom' --no-check-certificate
    PLA · 2010-09-26 14:47:13 3
  • Tail all logs that are opened by all java processes. This is helpful when you are on a new environment and you do not know where the logs are located. Instead of java you can put any process name. This command does work only for Linux. The list of all log files opened by java process: sudo ls -l $(eval echo "/proc/{$(echo $(pgrep java)|sed 's/ /,/')}/fd/")|grep log|sed 's/[^/]* //g'


    -1
    sudo ls -l $(eval echo "/proc/{$(echo $(pgrep java)|sed 's/ /,/')}/fd/")|grep log|sed 's/[^/]* //g'|xargs -r tail -f
    vutcovici · 2010-07-30 18:20:00 0
  • Takes all .flac directories, feeds them into a simple transcode pipeline to spit out .wavs with the same name (but correct extension).


    5
    for i in *.flac; do gst-launch filesrc location="$i" ! flacdec ! wavenc ! filesink location="${i%.flac}.wav"; done
    JamesHarrison · 2010-07-17 22:48:22 0
  • I have come across a situation in the past where someone has unlinked a file by running an 'rm' command against it while it was still being written to by a running process. The problem manifested itself when a 'df' command showed a filesystem at 100%, but this did not match the total value of a 'du -sk *'. When this happens, the process continues to write to the file but you can no longer see the file on the filesystem. Stopping and starting the process will, more often than not, get rid of the unlinked file, however this is not always possible on a live server. When you are in this situation you can use the 'lsof' command above to get the PID of the process that owns the file (in the sample output this is 23521). Run the following command to see a sym-link to the file (marked as deleted): cd /proc/23521/fd && ls -l Truncate the sym-link to regain your disk space: > /proc/23521/fd/3 I should point out that this is pretty brutal and *could* potentially destabilise your system depending on what process the file belongs to that you are truncating. Show Sample Output


    16
    lsof +L1
    dopeman · 2010-07-14 17:21:01 2
  • [ 2000 -ge "$(free -m | awk '/buffers.cache:/ {print $4}')" ] returns true if less than 2000 MB of RAM are available, so adjust this number to your needs. [ $(echo "$(uptime | awk '{print $10}' | sed -e 's/,$//' -e 's/,/./') >= $(grep -c ^processor /proc/cpuinfo)" | bc) -eq 1 ] returns true if the current machine load is at least equal to the number of CPUs. If either of the tests returns true we wait 10 seconds and check again. If both tests return false, i.e. 2GB are available and machine load falls below number of CPUs, we start our command and save it's output in a text file. The ( ( ... ) & ) construct lets the command run in background even if we log out. See http://www.commandlinefu.com/commands/view/3115/ .


    4
    ( ( while [ 2000 -ge "$(free -m | awk '/buffers.cache:/ {print $4}')" ] || [ $(echo "$(uptime | awk '{print $10}' | sed -e 's/,$//' -e 's/,/./') >= $(grep -c ^processor /proc/cpuinfo)" | bc) -eq 1 ]; do sleep 10; done; my-command > output.txt ) & )
    michelsberg · 2010-07-13 09:12:11 0
  • Tired copy paste to get opcode from objdump huh ? Get more @ http://gunslingerc0de.wordpress.com Show Sample Output


    4
    objdump -d ./PROGRAM|grep '[0-9a-f]:'|grep -v 'file'|cut -f2 -d:|cut -f1-6 -d' '|tr -s ' '|tr '\t' ' '|sed 's/ $//g'|sed 's/ /\\x/g'|paste -d '' -s |sed 's/^/"/'|sed 's/$/"/g'
    gunslinger_ · 2010-07-11 15:44:48 4
  • Control (stop, start, restart) a Windows Service from a Linux machine which has the `net` command (provided by samba). Show Sample Output


    4
    net rpc -I ADDRESS -U USERNAME%PASSWORD service {stop|start} SVCNAME
    f0rk · 2010-06-29 17:12:36 5
  • This is a shortcut to tar up all files matching a wildcard. Tar doesn't have the --include (apparently).


    1
    tar -czf ../header.tar.gz $(find . -name *.h)
    unixmonkey10524 · 2010-06-27 23:44:48 1
  • A little aptitude magic. Note: this will remove images AND headers. If you just want to remove images: aptitude remove ?and(~i~nlinux-im ?not(~n`uname -r`)) I used this in zsh without any problems. I'm not sure how other shells will interpret some of the special characters used in the aptitude search terms. Use -s to simulate.


    2
    aptitude remove ?and(~i~nlinux-(im|he) ?not(~n`uname -r`))
    dbbolton · 2010-06-11 22:57:09 0

  • -4
    aptitude purge linux-image | grep ^i | grep -v $(uname -r)
    lgallardo · 2010-06-11 22:20:42 0
  • TIMTOWTDI


    1
    perl -e 'chomp($k=`uname -r`); for (</boot/vm*>) {s/^.*vmlinuz-($k)?//; $l.="linux-image-$_ ";} system "aptitude remove $l";'
    dbbolton · 2010-06-10 22:16:47 0
  • This should do the same thing and is about 70 chars shorter. Show Sample Output


    8
    aptitude remove $(dpkg -l|egrep '^ii linux-(im|he)'|awk '{print $2}'|grep -v `uname -r`)
    dbbolton · 2010-06-10 21:23:00 4

  • 5
    while inotifywait -r -e MODIFY dir/; do make; done;
    prayer · 2010-06-08 23:34:00 2
  • Uses inotifywait from inotify-tools ( http://wiki.github.com/rvoicilas/inotify-tools/ ), that is compatible only with linux. Usefull when you work with files that have to be compiled.. latex, haml, c..


    15
    while true; do inotifywait -r -e MODIFY dir/ && make; done;
    fain182 · 2010-06-04 17:07:03 0
  • Get colorful fortunes dictated by an ASCII cow. For full enjoyment you'll need to have color setup enabled for your terminal.


    -6
    cowsay `fortune` | toilet --metal -f term
    seattlegaucho · 2010-06-03 21:48:54 1
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