All commands (14,187)

  • make password randomly, default 8 char


    -1
    genpass() { local h x y;h=${1:-8};x=( {a..z} {A..Z} {0..9} );y=$(echo ${x[@]} | tr ' ' '\n' | shuf -n$h | xargs);echo -e "${y// /}"; }
    twfcc · 2009-10-24 04:05:42 4
  • Use multiple patterns with grep -v. So you can print all lines in a file except those containing the multiple patterns you specify.


    16
    grep 'test' somefile | grep -vE '(error|critical|warning)'
    zlemini · 2009-10-23 23:21:36 12
  • Alternative to the ping check if your firewall blocks ping. Uses curl to get the landing page silently, or fail with an error code. You can probably do this with wget as well. Show Sample Output


    2
    curl -fs brandx.jp.sme 2&>1 > /dev/null || echo brandx.jp.sme ping failed | mail -ne -s'Server unavailable' joker@jp.co.uk
    mccalni · 2009-10-23 14:29:06 4
  • Strip my code to: wmctrl -o 0,0 # autorotates to the first face. In fact [0-1279],0 wmctrl - 1280,0 # goes to the second face wmctrl -o 2560,0 # goes to the third face, and so on. # Use multiples of the horizontal display resolution. My example work for 1280x800 display, been 1280 the number of interest. Tweak the number, try a biiiig one and see your cube spinning... I put a complex example to show how fun things can be, even for my ademco and paradox alarm central network advisor interface xpto etc. It rotates two faces, print the alarm message, and goes back tho where it was. Tested on BIGLINUX 4.2, equivalent to ubuntu LTS hardy. Do not forget to activate 3D efects ( compiz cube ) Show Sample Output


    5
    wmctrl -o 2560,0 ;sleep 2 ; echo "FIRE 001" | osd_cat -o 470 -s 8 -c red -d 10 -f -*-bitstream\ vera\ sans-*-*-*--250-*-*-*-*-*-*-* ; sleep 1; wmctrl -o 0,0
    m33600 · 2009-10-23 10:00:51 17
  • already described on the other two versions, this one uses ascii characters on game style to display elapsed time. Show Sample Output


    0
    export I=$(date +%s); watch -t -n 1 'T=$(date +%s);E=$(($T-$I));hours=$((E / 3600)) ; seconds=$((E % 3600)) ; minutes=$((seconds / 60)) ; seconds=$((seconds % 60)) ; echo $(printf "%02d:%02d:%02d" $hours $minutes $seconds) | toilet -f shadow'
    m33600 · 2009-10-23 07:56:30 10
  • Variation of the theme, this one blinks in low profile on top level of X, ie, it is visible, indeed small. Try changing fonts and sizes of osd_cat


    0
    export I=$(date +%s); watch -t -n 1 'T=$(date +%s);E=$(($T-$I));hours=$((E / 3600)) ; seconds=$((E % 3600)) ; minutes=$((seconds / 60)) ; seconds=$((seconds % 60)) ; echo $(printf "%02d:%02d:%02d" $hours $minutes $seconds) | osd_cat -o 20 -d 1 -p bottom'
    m33600 · 2009-10-23 07:47:11 3
  • Works on real time clock, unix time based, decrementing the actual time from initial time saved in an environment variable exported to child process inside watch Shows elapsed time from start of script in hh:mm:ss format Non afected by system slow down due to the use of date.


    3
    export I=$(date +%s); watch -t -n 1 'T=$(date +%s);E=$(($T-$I));hours=$((E / 3600)) ; seconds=$((E % 3600)) ; minutes=$((seconds / 60)) ; seconds=$((seconds % 60)) ; echo $(printf "%02d:%02d:%02d" $hours $minutes $seconds)'
    m33600 · 2009-10-23 07:31:44 8
  • simple function , floating point number is supported.


    12
    calc(){ awk "BEGIN{ print $* }" ;}
    twfcc · 2009-10-23 06:03:07 52
  • My firefox overheats my cpu, sometimes above 90 degrees Celsius ( hence the name? ) To keep an eye on temperature, I put this command inside KAlarm ( a kind of cron) to be repeated every minute, for 5 seconds, color red ( default for osd_cat). Its pretty, ultra small, displays a micro 2 lines text on every desktop and over everything and do not steal focus or interrupt any task. I get the information passively, in the low profile bottom of the screen. Of course you can use it inside a terminal. Just do it: watch -n 60 'acpi -t | osd_cat -p bottom'


    2
    acpi -t | osd_cat -p bottom
    m33600 · 2009-10-23 05:22:01 3
  • Usefull as a light blink to remember events, mails, intrusions, etc... yet another output Since nobody ever uses the scroll lock function... Usefull to interface a linux system with some hardware, for example, opto interfacing the keyboard led to a relay to remotely reset, etc. ( a simple LDR glued over the LED will do the trick ) xset led 3 turns on the third led, ie, Scroll lock xset -led 3 turns it off xset led 1 turns on Numerical Lock led ( doesn t work on all computer ) xset led 2 turns on Caps Lock led ( idem ) Using it as a reset watchdog, the relay expected light pulses. Shall the computer hangs, the relay releases and reset the machine ( discharge of a capacitor ) ;-)


    5
    xset led 3
    m33600 · 2009-10-23 00:25:56 15
  • If you omit the function name, the command will display all definitions Show Sample Output


    5
    declare -f [ function_name ]
    haivu · 2009-10-22 17:52:47 6
  • If you issue the "set" command, you'll see a list of variables and functions. This command displays just those functions' names. Show Sample Output


    1
    set | fgrep " ()"
    haivu · 2009-10-22 17:48:54 6
  • Handled all within awk. Takes the value from $PWD and constructs directory structures and runs commands against them. The gsub() call is not necessary, but added for better visibility. If a variable DIR is given on the awk command-line, then that directory is used instead: awk -vDIR=$HOME/.ssh 'BEGIN{dir=DIR?...}' Show Sample Output


    -1
    awk 'BEGIN{dir=DIR?DIR:ENVIRON["PWD"];l=split(dir,parts,"/");last="";for(i=1;i<l+1;i++){d=last"/"parts[i];gsub("//","/",d);system("ls -ld \""d"\"");last=d}}'
    arcege · 2009-10-22 16:28:07 5
  • note the xargs at the end


    5
    shuf -i 1-49 | head -n6 | sort -n| xargs
    ioggstream · 2009-10-22 12:54:08 93
  • Can easily be scripted in order to show permission "tree" from any folder. Can also be formated with column -t { pushd .> /dev/null; cd /; for d in `echo $OLDPWD | sed -e 's/\// /g'`; do cd $d; echo -n "$d "; ls -ld .; done; popd >/dev/null ; } | column -t from http://www.commandlinefu.com/commands/view/3731/using-column-to-format-a-directory-listing Show Sample Output


    0
    pushd .> /dev/null; cd /; for d in `echo $OLDPWD | sed -e 's/\// /g'`; do cd $d; echo -n "$d "; ls -ld .; done; popd >/dev/null
    syladmin · 2009-10-22 12:32:11 3

  • 7
    echo $(shuf -i 1-49 | head -n6 | sort -n)
    twfcc · 2009-10-22 06:48:20 4
  • One character less...


    0
    flip -u <filenames>
    linuxmonkey · 2009-10-21 21:25:43 3
  • atime and mtime timestamps of $FILE2 is changed according to the ones of $FILE1. If $FILE2 doesn't exist is created. Show Sample Output


    2
    touch -r "$FILE1" "$FILE2"
    kobayashison · 2009-10-21 13:53:59 6

  • 0
    shopt -s dotglob
    sharfah · 2009-10-21 13:31:20 3
  • This could be added to .bashrc. Background: Linux usually saves history only on clean exit of shell. If shell ends unclean, history is lost. Also numerous terminals might confuse their history. With this variable set, history is immedeately written, accessible to all other open shells.


    2
    PROMPT_COMMAND="history -a"
    danam · 2009-10-21 12:33:25 4
  • set directly the wallpaper on windowmaker , use this command with display of imagemagick :) Show Sample Output


    1
    wmsetbg -s -u path_to_wallpaper
    eastwind · 2009-10-21 11:23:54 4
  • syntax : mencoder mf://filemask -mf option availble for mf : * w=value : the width of the output, by d?fault : autodetected * h=value : height of the output, by default : autodetected * fps=value : framerate of the output, by default : 25 * type=value : file format type input , avaible: jpeg, png, tga, sgi


    -1
    mencoder mf://image1.jpg,image2.jpg,image3.jpg -mf w=800:h=600:fps=25:type=jpeg -ovc copy -oac copy -o output.avi
    eastwind · 2009-10-21 09:17:22 3
  • syntax : mencoder mf://filemask -mf option availble for mf : * w=value : the width of the output, by d?fault : autodetected * h=value : height of the output, by default : autodetected * fps=value : framerate of the output, by default : 25 * type=value : file format type input , avaible: jpeg, png, tga, sgi Show Sample Output


    0
    mencoder mf://*.jpg -mf w=800:h=600:fps=25:type=jpeg -ovc lavc -lavcopts vcodec=mpeg4 -oac copy -o output.avi
    eastwind · 2009-10-21 09:14:04 3
  • Convert those .mov files that your digital camera makes to .avi Adjust the bitrate (-b) to get the appropriate file size. A larger bitrate produces a larger (higher quality) .avi file and smaller bitrate produces a smaller (lower quality) .avi file. Requires ffmpeg (see man page for details) (tested with canon camera MOV files) Other examples: ffmpeg -i input.mov -sameq -vcodec msmpeg4v2 -acodec pcm_u8 output.avi ffmpeg -i input.mov -b 1024k -vcodec msmpeg4v2 -acodec pcm_u8 output.avi


    1
    ffmpeg -i input.mov -b 4096k -vcodec msmpeg4v2 -acodec pcm_u8 output.avi
    oracular · 2009-10-21 05:44:31 9
  • Just one character longer than the sed version ('FNR==5' versus -n 5p). On my system, without using "exit" or "q", the awk version is over four times faster on a ~900K file using the following timing comparison: testfile="testfile"; for cmd in "awk 'FNR==20'" "sed -n '20p'"; do echo; echo $cmd; eval "$cmd $testfile"; for i in {1..3}; do time for j in {1..100}; do eval "$cmd $testfile" >/dev/null; done; done; done Adding "exit" or "q" made the difference between awk and sed negligible and produced a four-fold improvement over the awk timing without the "exit". For long files, an exit can speed things up: awk 'FNR==5{print;exit}' <file>


    2
    awk 'FNR==5' <file>
    dennisw · 2009-10-20 22:52:41 5
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Short one line while loop that outputs parameterized content from one file to another
The above is an example of grabbing only the first column. You can define the start and end points specifically by chacater position using the following command: $ while read l; do echo ${l:10:40}; done < three-column-list.txt > column-c10-c40.txt Of course, it doesn't have to be a column, or extraction, it can be replacement $ while read l; do echo ${l/foo/bar}; done < list-with-foo.txt > list-with-bar.txt Read more about parameter expansion here: http://wiki.bash-hackers.org/syntax/pe Think of this as an alternative to awk or sed for file operations

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"

show git logging
shows some logging for the git repo.

Search commandlinefu from the command line
There's probably a more efficient way to do this rather than the relatively long perl program, but perl is my hammer, so text processing looks like a nail. This is of course a lot to type all at once. You can make it better by putting this somewhere: $ clf () { (curl -d "q=$@" http://www.commandlinefu.com/search/autocomplete 2>/dev/null) | egrep 'autocomplete|votes|destination' | perl -pi -e 's/$/\n\n/g;s/^ +|\([0-9]+ votes,//g;s/^\//http:\/\/commandlinefu.com\//g'; } Then, to look up any command, you can do this: $ clf diff This is similar to http://www.colivre.coop.br/Aurium/CLFUSearch except that it's just one line, so more in the spirit of CLF, in my opinion.

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

Mysql extended status
Useful when checking MySQL status.

save man-page as pdf

check open ports without netstat or lsof

Advanced python tracing
Trace python statement execution and syscalls invoked during that simultaneously

edit, view or execute last modified file with a single key-press
Copy this function to command line, press 'Enter' 'f'' 'Enter' to execute (sentence on the left written only for newbies). Hint 'e|x|v|1..9' in front of displayed last modified file name means: "Press 'e' for edit,'x' for execute,'v' for view or a digit-key '1..9' to touch one file from the recent files list to be last modified" and suggested (hidden files are listed too, else remove 'a' from 'ls -tarp' statement if not intended). If you find this function useful you can then rename it if needed and append or include into your ~/.bashrc config script. With the command $ . ~/.bashrc the function then can be made immediately available. In the body of the function modifications can be made, i.e. replaced joe editor command or added new option into case statement, for example 'o) exo-open $h;;' command for opening file with default application - or something else (here could not be added since the function would exceed 255 chars). To cancel execution of function started is no need to press Ctrl-C - if the mind changed and want to leave simple Enter-press is enough. Once defined, this function can with $ typeset -f f command be displayed in easy readable form


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