Commands using sh (66)


  • 17
    env PS4=' ${BASH_SOURCE}:${LINENO}(${FUNCNAME[0]}) ' sh -x /etc/profile
    oernii2 · 2009-10-07 14:44:59 4
  • I needed a way to search all files in a web directory that contained a certain string, and replace that string with another string. In the example, I am searching for "askapache" and replacing that string with "htaccess". I wanted this to happen as a cron job, and it was important that this happened as fast as possible while at the same time not hogging the CPU since the machine is a server. So this script uses the nice command to run the sh shell with the command, which makes the whole thing run with priority 19, meaning it won't hog CPU processing. And the -P5 option to the xargs command means it will run 5 separate grep and sed processes simultaneously, so this is much much faster than running a single grep or sed. You may want to do -P0 which is unlimited if you aren't worried about too many processes or if you don't have to deal with process killers in the bg. Also, the -m1 command to grep means stop grepping this file for matches after the first match, which also saves time. Show Sample Output


    10
    sh -c 'S=askapache R=htaccess; find . -mount -type f|xargs -P5 -iFF grep -l -m1 "$S" FF|xargs -P5 -iFF sed -i -e "s%${S}%${R}%g" FF'
    AskApache · 2009-10-02 05:03:10 0
  • This is useful if you'd like to see the output of a script while you edit it. Each time you save the file the command is executed. I thought for sure something like this already exists - and it probably does. I'm on an older system and tend to be missing some useful things. Examples: ontouchdo yourscript 'clear; yourscript somefiletoparse' Edit yourscript in a separate window and see new results each time you save. ontouchdo crufty.html 'clear; xmllint --noout crufty.html 2>&1 | head' Keep editing krufty.html until the xmllint window is empty. Note: Mac/bsd users should use stat -f%m. If you don't have stat, you can use perl -e '$f=shift; @s=stat($f); print "$s[9]\n";' $1


    10
    ontouchdo(){ while :; do a=$(stat -c%Y "$1"); [ "$b" != "$a" ] && b="$a" && sh -c "$2"; sleep 1; done }
    putnamhill · 2010-10-22 23:25:12 3

  • 7
    find . -type d -exec env d="$dest_root" sh -c ' exec mkdir -p -- "$d/$1"' '{}' '{}' \;
    hahnst · 2009-08-03 12:21:37 1
  • or echo '127.0.0.1 facebook.com' | sudo tee -a /etc/hosts Do not execute this command if you don't know what you are doing.


    7
    sudo sh -c "echo '127.0.0.1 www.facebook.com' >> /etc/hosts"
    devalnor · 2012-01-16 14:06:51 2
  • Bash process substitution which curls the website 'hashbang.sh' and executes the shell script embedded in the page. This is obviously not the most secure way to run something like this, and we will scold you if you try. The smarter way would be: Download locally over SSL > curl https://hashbang.sh >> hashbang.sh Verify integrty with GPG (If available) > gpg --recv-keys 0xD2C4C74D8FAA96F5 > gpg --verify hashbang.sh Inspect source code > less hashbang.sh Run > chmod +x hashbang.sh > ./hashbang.sh


    5
    sh <(curl hashbang.sh)
    lrvick · 2015-03-15 21:02:01 2
  • This is a commodity one-liner that uses ShellCheck to assure some quality on bash and sh scripts under a specific directory. It ignores the files in .git directory. Just substitute "./.git/*" with "./.svn/*" for older and booring centralized version control. Just substitute ShellCheck with "rm" if your scripts are crap and you want to get rid of them :)


    5
    find . -type f ! -path "./.git/*" -exec sh -c "head -n 1 {} | egrep -a 'bin/bash|bin/sh' >/dev/null" \; -print -exec shellcheck {} \;
    brx75x · 2017-03-16 08:43:56 3

  • 3
    find $MAILDIR/ -type f -printf '%T@ %p\n' | sort --reverse | sed -e '{ 1,100d; s/[0-9]*\.[0-9]* \(.*\)/\1/g }' | xargs -i sh -c "cat {}&&rm -f {}" | gzip -c >>ARCHIVE.gz
    maergil · 2009-08-11 20:12:15 0
  • this command works with one gziped file per table, and restore 4 tables in parallel. Show Sample Output


    3
    find -print0 | xargs -0 -n 1 -P 4 -I {} sh -c "zcat '{}' | mysql nix"
    skygreg · 2009-08-25 15:05:55 2
  • USAGE: $ sudor your command This command uses a dirty hack with history, so be sure you not turned it off. WARNING! This command behavior differ from other commands. It more like text macro, so you shouldn't use it in subshells, non-interactive sessions, other functions/aliases and so on. You shouldn't pipe into sudor (any string that prefixes sudor will be removed), but if you really want, use this commands: proceed_sudo () { sudor_command="`HISTTIMEFORMAT=\"\" history 1 | sed -r -e 's/^.*?sudor//' -e 's/\"/\\\"/g'`" ; pre_sudor_command="`history 1 | cut -d ' ' -f 5- | sed -r -e 's/sudor.*$//' -e 's/\"/\\\"/g'`"; if [ -n "${pre_sudor_command/ */}" ] ; then eval "${pre_sudor_command%| *}" | sudo sh -c "$sudor_command"; else sudo sh -c "$sudor_command" ;fi ;}; alias sudor="proceed_sudo # "


    3
    proceed_sudo () { sudor_command="`HISTTIMEFORMAT=\"\" history 1 | sed -r -e 's/^.*?sudor//' -e 's/\"/\\\"/g'`" ; sudo sh -c "$sudor_command"; }; alias sudor="proceed_sudo # "
    mechmind · 2010-06-29 14:56:29 0
  • Do the same as pssh, just in shell syntax. Put your hosts in hostlist, one per line. Command outputs are gathered in output and error directories.


    3
    xargs -n1 -P100 -I{} sh -c 'ssh {} uptime >output/{} 2>error/{}' <hostlist
    dooblem · 2010-08-20 11:03:11 0
  • This command converts filenames with embedded spaces in the current directory replacing spaces with the underscore ("_") character. Show Sample Output


    2
    ls -1 | grep " " | awk '{printf("mv \"%s\" ",$0); gsub(/ /,"_",$0); printf("%s\n",$0)}' | sh # rename filenames: spaces to "_"
    mpb · 2009-03-15 18:42:43 13
  • Manages everything through one sed script instead of pipes of greps and awks. Quoting of shell variables is generally easier within a sed script.


    2
    svn log fileName | sed -ne "/^r\([0-9][0-9]*\).*/{;s//\1/;s/.*/svn cat fileName@& > fileName.r&/p;}" | sh -s
    arcege · 2009-09-04 17:23:45 0
  • For each directory from the current one, list the counts of files in each of these directories. Change the -maxdepth to drill down further through directories. Show Sample Output


    2
    find . -maxdepth 1 -type d -exec sh -c "printf '{} ' ; find '{}' -type f -ls | wc -l" \;
    HerbCSO · 2013-07-29 19:46:35 0
  • url can be like any one of followings: url="MejbOFk7H6c" url="http://youtu.be/MejbOFk7H6c" url="https://youtube.com/watch?feature=player_embedded&v=MejbOFk7H6c#t" url="//www.youtube.com/v/MejbOFk7H6c?hl=ru_RU&version=3&rel=0" url="http://www.youtube.com/embed/MejbOFk7H6c?feature=player_embedded" If url mismatching, whole url will be returned. Show Sample Output


    2
    sh -c 'url="http://youtu.be/MejbOFk7H6c"; vid="`for i in ".*youtu\.be/\([^\/&?#]\+\)" ".*youtu.\+v[=/]\([^\/&?#]\+\)" ".*youtu.\+embed/\([^\/&?#]\+\)"; do expr "${url}" : "${i}"; done`"; if [ -n "${vid}" ]; then echo ${vid}; else echo "${url}"; fi'
    qwertyroot · 2013-09-04 19:33:09 0
  • This has been my "sysupgrade" alias since ca. 2006, first used on Debian Sid, then Sabayon, and it still does its duty on Mint nowadays without breaking stuff.


    2
    sudo sh -c "aptitude update; aptitude -DrVWZ full-upgrade; aptitude autoclean; exit"
    lordtoran · 2015-09-28 23:48:05 0
  • Get information of volume labels of bitlocker volumes, even if they are encrypted and locked (no access to filesystem, no password provided). Note that the volume labels can have spaces, but only if you name then before encryption. Renaming a bitlocker partition after being encrypted does not have the same effect as doing it before. Show Sample Output


    2
    sudo echo "BitLocker Volume labels:" && sudo dislocker-find | xargs -I{} sh -c 'echo -n "{} ->+ " ; sudo dislocker-metadata -V {} | grep string' | sed 's/+.*string://' | sed "s/'[^ ]* /\"/g" | sed 's/\ [^ ]*$/"/'
    bugmenot · 2018-04-29 01:00:11 0
  • If the remote doesn't export its desktop (eg fluxbox, blackbox etc) then you need to run a x11vnc server there and a vncviewer at the local end. This command does the lot for you - it assumes that you can 'ssh' to the box without a password and that x11vnc is installed at the remote end.


    1
    rdp() { ssh $1 sh -c 'PATH=$PATH:/usr/local/bin; x11vnc -q -rfbauth ~/.vnc/passwd -display :0' & sleep 4; vncviewer $1:0 & }
    bhepple · 2009-11-25 07:21:02 0
  • I used this command to recursively gather all mp3 files that were previously imported into their own directories (sorted by band name) in Songbird.


    1
    find . -name '*.mp3' -type f -exec sh -c 'exec cp -f "$@" /home/user/dir' find-copy {} +
    mariusz · 2009-12-08 19:31:16 1
  • Grabs the cmdline used to execute the process, and the environment that the process is being run under. This is much different than the 'env' command, which only lists the environment for the shell. This is very useful (to me at least) to debug various processes on my server. For example, this lets me see the environment that my apache, mysqld, bind, and other server processes have. Here's a function I use: aa_ps_all () { ( cd /proc && command ps -A -opid= | xargs -I'{}' sh -c 'test $PPID -ne {}&&test -r {}/cmdline&&echo -e "\n[{}]"&&tr -s "\000" " "<{}/cmdline&&echo&&tr -s "\000\033" "\nE"<{}/environ|sort&&cat {}/limits' ); } From my .bash_profile at http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html Show Sample Output


    1
    cd /proc&&ps a -opid=|xargs -I+ sh -c '[[ $PPID -ne + ]]&&echo -e "\n[+]"&&tr -s "\000" " "<+/cmdline&&echo&&tr -s "\000\033" "\nE"<+/environ|sort'
    AskApache · 2010-10-22 02:34:33 3

  • 1
    svn status | grep '^?' | sed -e 's/^? */svn add "/g' -e 's/$/"/g'|sh ; svn status | grep '^!' | sed -e 's/^! */svn delete "/g' -e 's/$/"/g'|sh
    ironmarc · 2010-11-18 09:57:45 0

  • 1
    git branch -r | awk -F'/' '{print "git fetch "$1,$2}' | xargs -I {} sh -c {}
    cakyus · 2014-10-25 07:36:50 2
  • Linux offers an interesting option to restrict the use of dmesg. It is available via /proc/sys/kernel/dmesg_restrict. You can check the status with: cat /proc/sys/kernel/dmesg_restrict Alternatively you can use sysctl: sudo sysctl -w kernel.dmesg_restrict=1 To make your change persistent across reboot, edit a fille in /etc/sysctl.d/.


    1
    sudo sh -c 'echo 1 > /proc/sys/kernel/dmesg_restrict'
    Blacksimon · 2015-03-13 20:54:45 0
  • Benchmark a SQL query against MySQL Server. The example runs the query 10 times, and you get the average runtime in the output. To ensure that the query does not get cached, use `RESET QUERY CACHE;` on top in the query file. Show Sample Output


    1
    perf stat -r 10 sh -c "mysql > /dev/null < query.sql"
    particleflux · 2018-05-03 12:20:03 0

  • 1
    find /path -name '*.pdf' -exec sh -c 'pdftotext "{}" - | grep --with-filename --label="{}" --color "your pattern"' \;
    HaoZeke · 2018-08-13 07:31:54 0
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Exclude inserting a table from a sql import
Starting with a large MySQL dump file (*.sql) remove any lines that have inserts for the specified table. Sometimes one or two tables are very large and uneeded, eg. log tables. To exclude multiple tables you can get fancy with sed, or just run the command again on subsequently generated files.

Install Linux Kernel Headers on Debian-based systems
Install the Linux kernel headers for currently running kernel version on Debian-based systems via apt-get

Generate a random password 30 characters long
This command is similar to the alternate, except with head(1), you can pick as many passwords as you wish to generate by changing the number of lines you wish to preview.

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"

Check if a string is into a variable
Returns true (0) if the string is into $var, or false (1) if not.

continuously print string as if being entered from the keyboard
Cycles continuously through a string printing each character with a random delay less than 1 second. First parameter is min, 2nd is max. Example: 1 3 means sleep random .1 to .3. Experiment with different values. The 3rd parameter is the string. The sleep will help with battery life/power consumption. $ cycle 1 3 $(openssl rand 100 | xxd -p) Fans of "The Shining" might get a kick out of this: $ cycle 1 4 ' All work and no play makes Jack a dull boy.'

Recursive replace of directory and file names in the current directory.
This should work anywhere perl and grep is available. :P

run a VirtualBox virtual machine without a gui
you can launch a VirtualBox VM from the command line using VBoxManage, but that invokes it in a gui environment. If you want to just fire off your VM in the background, use VBoxHeadless as shown. To get the names and UUIDs of your VirtualBox VMs, type: $ VBoxManage list

Have an ssh session open forever
Open a ssh session opened forever, great on laptops losing Internet connectivity when switching WIFI spots.

Find last reboot time
Specific to OSX.


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