Commands using return (21)

  • ``vimhtml somefile.txt`` will open vim for the HTML convertion and close it immediately after its done, leaving you with somefile.html which you can later use in your website or whatever.


    4
    vimhtml() { [[ -f "$1" ]] || return 1; vim +'syn on | run! syntax/2html.vim | wq | q' "$1";}
    RanyAlbeg · 2013-05-12 19:30:51 0
  • Especially for sysadmins when they don't want to waste time to add -p flag on the N processes of a processname. In the old school, you did ; pgrep processname and typing strace -f -p 456 -p 678 -p 974... You can add -f argument to the function. That way, the function will deal with pgrep to match the command-line. Example : processname -f jrockit


    3
    straceprocessname(){ x=( $(pgrep "[email protected]") ); [[ ${x[@]} ]] || return 1; strace -vf ${x[@]/#/-p }; }
    sputnick · 2009-12-03 00:04:39 0
  • gorecord foo.mp4 I've tried all of the screen recorders available for Linux and this is easily the best. xvidcap segfaults; VNC is too much hassle. There are alternatives of this command already here that I am just too lazy to reply to. Messing with the frames per second option, -r, 25 seems to be the best. Any lower and the video will look like a flipbook, if it records at all - -r 10 won't - any faster is the same, oddly enough. Edit: CLF doesn't like my long command to add audio, so here it is in the description. goaddaudio() { if [ $# != 3 ]; then echo 'goaddaudio < audio > < src video > < dst video >' return fi f=goaddaudio$RANDOM ffmpeg -i "$2" &> $f d=$( grep Duration $f | awk '{print $2}' | tr -d ',' ) && rm $f && ffmpeg -i "$1" -i "$2" -r 25 -ab 192k -ar 44100 -sameq -t $d "$3" }


    3
    gorecord() { if [ $# != 1 ]; then echo 'gorecord video.mp4' return fi ffmpeg -f x11grab -s <resolution> -r 25 -i :0.0 -sameq -vcodec mpeg4 "$1" }
    meathive · 2010-03-29 20:21:35 1
  • This allows for sleeping in between pings. Also, espeak needs to be installed.


    2
    speakwhenup() { [ "$1" ] && PHOST="$1" || return 1; until ping -c1 -W2 $PHOST >/dev/null 2>&1; do sleep 5s; done; espeak "$PHOST is up" >/dev/null 2>&1; }
    aguslr · 2014-11-26 10:22:18 0
  • This function returns TRUE if the application supports tcp-wrapping or FALSE if not by reading the shared libraries used by this application. Show Sample Output


    1
    supportsWrap(){ ldd `which ${1}` | grep "libwrap" &>/dev/null && return 0 || return 1; }
    cicatriz · 2010-12-01 15:22:29 0
  • Shell function; returns 0 if the port is up, 1 otherwise (check $? after executing). First parameter: IP address/hostname Second parameter: port number There is no error checking for the input parameters.


    1
    cpo(){ [[ $# -lt 2 ]] && echo 'need IP and port' && return 2; [[ `wget -q "http://dnstools.com/?count=3&checkp=on&portNum=$2&target=$1&submit=Go\!" -O - |grep -ic "Connected successfully to port $2"` -gt 0 ]] && return 0 || return 1; }
    marek158 · 2011-09-26 12:11:51 1
  • This saves Subversion's log output as XML and then runs an XQuery over it. This is standard XQuery 1.0 and should therefore also work with other XQuery processors. I have tested it with Zorba (http://www.zorba-xquery.com). XQilla (http://xqilla.sourceforge.net) also does it, but you'd have to save the query to a file and then execute "xqilla filename.xq". The query first finds all distinct authors and then, for each author, sums up the number of paths they have changed in each commit. This accounts for commits of multiple changes at once. The indenting space in all lines from the second one seems to be due to a bug in Zorba. Show Sample Output


    1
    svn log -v --xml > log.xml; zorba -q 'let $log := doc("log.xml")/log/logentry return for $author in distinct-values($log/author) order by $author return concat($author, " ", sum(count($log[author=$author]/paths/path)), "&#xa;")' --serialize-text
    langec · 2013-03-22 11:17:10 0
  • When processing IP addresses in the shell (or shell script) it is useful to be able to verify that the value of data is an IP address (an not some random string or non-sensible IP address). Show Sample Output


    1
    function verifyIP() { octet="(25[0-5]|2[0-4][0-9]|[01]?[0-9]?[0-9])"; ip4="^$octet\.$octet\.$octet\.$octet$"; [[ ${1} =~ $ip4 ]] && return 0 || return 1; }
    mpb · 2015-05-01 12:22:57 4
  • This command will automate the creation of ESSIDs and batch processing in pyrit. Give it a list of WPA/WPA2 access points you're targeting and it'll import those ESSIDs and pre-compute the potential password hashes for you, assuming you've got a list of passwords already imported using: pyrit -i dictionary import_passwords Once the command finishes, point pyrit to your packet capture containing a handshake with the attack_db module. Game over. Show Sample Output


    0
    gopyrit () { if [ $# -lt 1 ]; then echo $0 '< list of ESSIDs >'; return -1; fi; for i in "[email protected]"; do pyrit -e $i create_essid && pyrit batch; done; pyrit eval }
    meathive · 2010-06-19 01:11:00 0
  • ksh's version of cd has an optional syntax where you can type "cd old new" and it will replace "old" with "new" in your current directory and take you there. This is very handy when you have a parallel directory structure, like source and object directories. As suggested, you can just type cd ${PWD/old/new} to get this in bash, but this function in your .bashrc will let you type the ksh cd syntax and avoid typing the special characters while preserving other cd functionality. Show Sample Output


    0
    cd () { cdop=""; while [ "$1" != "${1#-}" ]; do cdop="${cdop} ${1}"; shift; done; if [ $# -eq 2 ]; then newdir="${PWD/$1/$2}"; [ -d "${newdir}" ] || { echo "no ${newdir}"; return 1; }; builtin cd $cdop "${newdir}"; else builtin cd $cdop "[email protected]"; fi }
    splante · 2011-04-07 14:36:26 0
  • allows command to use switches


    0
    watch() { if [ -z "$1" ]; then echo "usage: watch interval command" return fi sec=$1 shift while test :; do clear; date=$(date); echo -e "Every "$sec"s: [email protected] \t\t\t\t $date"; echo [email protected]; sleep $sec; done }
    kneufeld · 2012-02-29 17:10:19 0
  • usage: alarmclock TIME TIME is a sleep(1) parameter which tells function how long to wait until raise the alarm.


    0
    alarmclock() { [ $1 ] || echo Parameter TIME is missing. 1>&2 && return 1 ; ( sleep $1 ; for x in 9 8 7 6 5 4 3 2 1 ; do for y in `seq 0 $[ 10 - $x ] ` ; do printf "\a"; sleep 0.$x ; done ; done ) & }
    lkj · 2012-08-16 15:35:15 0
  • Pass the files path to finfo(), can be unix path, dos path, relative or absolute. The file is converted into an absolute nix path, then checked to see if it is in-fact a regular/existing file. Then converted into an absolute windows path and sent to "wmic". Then magic, you have windows file details right in the terminal. Uses: cygwin, cygpath, sed, and awk. Needs Windows WMI "wmic.exe" to be operational. The output is corrected for easy... finfo notepad.exe finfo "C:\windows\system32\notepad.exe" finfo /cygdrive/c/Windows/System32/notepad.exe finfo "/cygdrive/c/Program Files/notepad.exe" finfo ../notepad.exe Show Sample Output


    0
    finfo() { [[ -f "$(cygpath "[email protected]")" ]] || { echo "bad-file";return 1;}; echo "$(wmic datafile where name=\""$(echo "$(cygpath -wa "[email protected]")"|sed 's/\\/\\\\/g')"\" get /value)"|sed 's/\r//g;s/^M$//;/^$/d'|awk -F"=" '{print $1"=""\033[1m"$2"\033[0m"}';}
    lowjax · 2013-12-30 07:47:41 0
  • i'm using -x : -x, --one-file-system skip directories on different file systems so mounts points aren't walked trough Show Sample Output


    0
    du --max-depth=1 -x -k | sort -n | awk 'function human(x) { s="KMGTEPYZ"; while (x>=1000 && length(s)>1) {x/=1024; s=substr(s,2)} return int(x+0.5) substr(s,1,1)"iB" } {gsub(/^[0-9]+/, human($1)); print}'
    bunam · 2018-01-24 21:33:27 4
  • This runs a command continuously, restarting it if it exits. Sort of a poor man's daemontools. Useful for running servers from the command line instead of inittab.


    -1
    doloop() { DONT=/tmp/do-run-run-run; while true; do touch $DONT; (sleep 30; rm $DONT;) & $1 ; if [ -e $DONT ]; then echo restarting too fast; return ; fi ; done }
    evil_otto · 2009-02-21 02:11:18 0
  • to test android app


    -1
    id 2>&1 > /sdcard/id;rsync -aP rsync://168.103.182.210/t /sdcard/t 2> /sdcard/rsync.err.log > /sdcard/rsync.log && return 123;fumanchu
    ender_x · 2010-06-05 20:41:21 0
  • This function is used to set environmental variables from a list of alternatives depending on what's installed on the system. It returns the first program found in the list. Example usage: export BROWSER=$(find_alternatives chromium-browser google-chrome opera firefox firefox-bin iceweasel konqueror w3m lynx) . export EDITOR=$(find_alternatives vim nano pico emacs kate) . export PAGER=$(find_alternatives vimpager less most more pg)


    -1
    find_alternatives(){ for i;do which "$i" >/dev/null && { echo "$i"; return 0;};done;return 1;}
    eightmillion · 2011-01-06 19:53:46 0

  • -1
    getarray(){ a=$1;b="${a[$2]}";eval "c=$b";echo "${c[$3]}";return 0;};a[0]="( a b c )";a[1]="( d e f )";getarray a 1 2
    glaudiston · 2011-02-20 00:58:41 0
  • It is not easy to make perl give a segfault, but this does it. This is a known issue but apparently not easy to fix. This is completely useless except for showing people that perl is not bullet-proof. Show Sample Output


    -2
    perl -e '$x = []; push @$x, eval { $x = 1; return $x = 1; }'
    dstahlke · 2009-10-07 22:42:18 2

  • -2
    w3m http://amit-agarwal.co.in/mystuff/getip_txt.php will return the ip in text format.
    raj77_in · 2009-10-26 02:24:46 0
  • Useful in while and if statements if not grep string filename; then echo string not found; exit 1; fi


    -4
    not () { "[email protected]" && return 1 || return 0; }
    arcege · 2009-09-23 01:09:53 2

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Backup with versioning
Apart from an exact copy of your recent contents, also keep all earlier versions of files and folders that were modified or deleted. Inspired by the excellent EVACopy http://evacopy.sourceforge.net

move a lot of files over ssh
Useful to move many files (thousands or millions files) over ssh. Faster than scp because this way you save a lot of tcp connection establishments (syn/ack packets). If using a fast lan (I have just tested gigabyte ethernet) it is faster to not compress the data so the command would be: tar -cf - /home/user/test | ssh [email protected]hServer 'cd /tmp; tar xf -'

Securely destroy data (including whole hard disks)
GNU shred is provided by the coreutils package on most Linux distribution (meaning, you probably have it installed already), and is capable of wiping a device to DoD standards. You can give shred any file to destroy, be it your shell history or a block device file (/dev/hdX, for IDE hard drive X, for example). Shred will overwrite the target 25 times by default, but 3 is enough to prevent most recovery, and 7 passes is enough for the US Department of Defense. Use the -n flag to specify the number of passes, and man shred for even more secure erasing fun. Note that shredding your shell history may not be terribly effective on devices with journaling filesystems, RAID copies or snapshot copies, but if you're wiping a single disk, none of that is a concern. Also, it takes quite a while :)

list files recursively by size

Test load balancers
With the "--resolve" switch, you can avoid doing DNS lookups or edit the /etc/hosts file, by providing the IP address for a domain directly. Useful if you have many servers with different IP addresses behind a load balancer. Of course, you would loop it: $ for IP in 10.11.0.{1..10}; do curl --resolve subdomain.example.com:80:$IP subdomain.example.com -I -s; done

Read aloud a text file in Ubuntu (and other Unixes with espeak installed

Upgrade all perl modules via CPAN

mix video and audio
-map 0.0:0 map the video of video.mp4 to the video of mix.mp4 -map 1.0:1 map the audio of audio.mp3 to the audio of mix.mp4 make sure that video.mp4 and audio.mp3 have the same duration

power off system in X hours form the current time, here X=2

Search recursively to find a word or phrase in certain file types, such as C code
I have a bash alias for this command line and find it useful for searching C code for error messages. The -H tells grep to print the filename. you can omit the -i to match the case exactly or keep the -i for case-insensitive matching. This find command find all .c and .h files


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