Commands tagged command (20)

  • This little function will smarten 'cd'. If you try to cd into a file (which I guess we all have done), it cd's into the directory of that file instead. I had to use nesten if's, to get cd to still work with 'cd' (to get to $HOME), 'cd -' (to get to last directory), and 'cd foo\ bar'. Show Sample Output


    9
    cd() { if [ -z "$1" ]; then command cd; else if [ -f "$1" ]; then command cd $(dirname "$1"); else command cd "$1"; fi; fi; }
    xeor · 2010-04-23 19:17:43 4
  • it is generally advised to avoid using which(1) whenever possible. which(1) is usually a csh(1) script, or sometimes a compiled binary. It's output is highly variable from operating system to operating system, so platform independent scripts could become quite complicated with the logic. On HP-UX 10.20, for example, it prints "no bash in /path /path /path ..."; on OpenBSD 4.1, it prints "bash: Command not found."; on Debian (3.1 through 5.0 at least) and SuSE, it prints nothing at all; on Red Hat 5.2, it prints "which: no bash in (/path:/path:...)"; on Red Hat 6.2, it writes the same message, but on standard error instead of standard output; and on Gentoo, it writes something on stderr. And given all these differences, it's still variable based on your shell. This is why POSIX is king. See http://mywiki.wooledge.org/BashFAQ/081 for more ways on avoiding which(1). Show Sample Output


    4
    command -v bash
    atoponce · 2011-09-26 10:17:41 4

  • 2
    history | awk '{a[$'$(echo "1 2 $HISTTIMEFORMAT" | wc -w)']++}END{for(i in a){print a[i] " " i}}' | sort -rn | head
    mrcomputer · 2010-06-03 16:06:09 1
  • While going through the source code for the well known ps command, I read about some interesting things.. Namely, that there are a bunch of different fields that ps can try and enumerate for you. These are fields I was not able to find in the man pages, documentation, only in the source. Here is a longer function that goes through each of the formats recognized by the ps on your machine, executes it, and then prompts you whether you would like to add it or not. Adding it simply adds it to an array that is then printed when you ctrl-c or at the end of the function run. This lets you save your favorite ones and then see the command to put in your .bash_profile like mine at : http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html Note that I had to do the exec method below in order to pause with read. t () { local r l a P f=/tmp/ps c='command ps wwo pid:6,user:8,vsize:8,comm:20' IFS=' '; trap 'exec 66 exec 66 $f && command ps L | tr -s ' ' >&$f; while read -u66 l >&/dev/null; do a=${l/% */}; $c,$a k -${a//%/} -A; yn "Add $a" && P[$SECONDS]=$a; done } Show Sample Output


    2
    for p in `ps L|cut -d' ' -f1`;do echo -e "`tput clear;read -p$p -n1 p`";ps wwo pid:6,user:8,comm:10,$p kpid -A;done
    AskApache · 2010-10-12 06:42:10 2
  • 5 helpful aliases for using the which utility, specifically for the GNU which (2.16 tested) that is included in coreutils. Which is run first for a command. Same as type builtin minus verbosity alias which='{ command alias; command declare -f; } | command which --read-functions --read-alias' Which (a)lias alias whicha='command alias | command which --read-alias' Which (f)unction alias whichf='command declare -f | command which --read-functions' Which e(x)ecutable file in PATH alias whichx='command which' Which (all) alias, function, builtin, and files in PATH alias whichall='{ command alias; command declare -f; } | command which --read-functions --read-alias -a' # From my .bash_profile http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html Show Sample Output


    2
    alias whichall='{ command alias; command declare -f; } | command which --read-functions --read-alias -a'
    AskApache · 2010-11-18 03:32:04 5
  • shell generate random strong password Show Sample Output


    2
    len=20; tr -dc A-Za-z0-9_ < /dev/urandom | head -c ${len} | xargs
    aysadk · 2019-04-16 20:20:46 2
  • * Add comment with # in your command * Later you can search that command on that comment with CTRL+R In the title command, you could search it later by invoking the command search tool by first typing CTRL+R and then typing "revert" Show Sample Output


    1
    svn up -r PREV # revert
    unixmonkey10719 · 2010-07-07 23:09:00 5
  • eg: Already running cmd sleep 120 Substitution cmd c=$(pgrep sleep) && sleep 5 && kill $c


    1
    c=$(pgrep <cmd>) && <new_cmd> && kill $c
    totti · 2011-09-14 19:58:30 0
  • Execute a process or list of commands in the given interval and output the difference in output. Show Sample Output


    1
    diffprocess () { diff <($*) <(sleep 3; $*); }
    totti · 2013-01-25 08:46:41 0
  • Top 30 History Command line with histogram display Show Sample Output


    1
    history|awk '{print $2}'|sort|uniq -c|sort -rn|head -30|awk '!max{max=$1;}{r="";i=s=100*$1/max;while(i-->0)r=r"#";printf "%50s %5d %s %s",$2,$1,r,"\n";}'
    injez · 2014-09-29 12:40:43 0
  • in this examp start htop command in tmux session over the shell cosole and set title for the tmux without doing it manuelly in tmux


    1
    tmux new-session -d -s "SessionName" "htop"
    aysadk · 2019-06-14 12:44:33 3
  • This will show you any links that a command follows (unlike 'file -L'), as well as the ultimate binary or script. Put the name of the command at the very end; this will be passed to perl as the first argument. For obvious reasons, this doesn't work with aliases or functions. Show Sample Output


    0
    perl -le 'chomp($w=`which $ARGV[0]`);$_=`file $w`;while(/link\b/){chomp($_=(split/`/,$_)[1]);chop$_;$w.=" -> $_";$_=`file $_`;}print "\n$w";' COMMAND_NAME
    dbbolton · 2010-07-30 19:26:35 2
  • Normally the bash builtin command 'set' displays all vars and functions. This just shows the vars. Useful if you want to see different output then env or declare or export. Alias 'sete' shows sets variables alias sete='set|sed -n "/^`declare -F|sed -n "s/^declare -f \(.*\)/\1 ()/p;q"`/q;p"' Alias setf shows the functions. alias setf='set|sed -n "/^`declare -F|sed -n "s/^declare -f \(.*\)/\1 ()/p;q"`/,\$p"' Also see: http://www.commandlinefu.com/commands/view/6899/print-all-environment-variables-including-hidden-ones At the very least, some cool sed commands! From my .bash_profile http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html Show Sample Output


    0
    alias sete='set|sed -n "/^`declare -F|sed -n "s/^declare -f \(.*\)/\1 ()/p;q"`/q;p"'
    AskApache · 2010-11-17 23:58:01 4
  • Using the output of 'ps' to determine CPU usage is misleading, as the CPU column in 'ps' shows CPU usage per process over the entire lifetime of the process. In order to get *current* CPU usage (without scraping a top screen) you need to pull some numbers from /proc/stat. Here, we take two readings, once second apart, determine how much IDLE time was spent across all CPUs, divide by the number of CPUs, and then subtract from 100 to get non-idle time. Show Sample Output


    0
    NUMCPUS=`grep ^proc /proc/cpuinfo | wc -l`; FIRST=`cat /proc/stat | awk '/^cpu / {print $5}'`; sleep 1; SECOND=`cat /proc/stat | awk '/^cpu / {print $5}'`; USED=`echo 2 k 100 $SECOND $FIRST - $NUMCPUS / - p | dc`; echo ${USED}% CPU Usage
    toxick · 2012-10-02 03:57:51 1
  • # AllInOne: Update what packages are available, upgrade to new versions, remove unneeded packages # (some are no longer needed, replaced by the ones from ap upgrade), check for dependencies # and clean local cached packages (saved on disk but not installed?,some are needed? [this only cleans unneeded unlike ap clean]). # aliases (copy into ~/.bashrc file): alias a='alias' a ap='apt-get' a r='ap autoremove -y' a up='ap update' a u='up && ap upgrade -y --show-progress && r && ap check && ap autoclean' # && means "and run if the previous succeeded", you can change it to ; to "run even if previous failed". I'm not sure if ap check should be before or after ap upgrade -y, you can also change the alias names. # To expand aliases in bash use ctrl alt e or see this ow.ly/zBKHs # For more useful aliases go to ow.ly/zBMOx


    0
    apt-get update && apt-get dist-upgrade -y --show-progress && apt-get autoremove -y && apt-get check && apt-get autoclean -y
    unixmonkey78577 · 2014-07-26 12:18:57 0

  • 0
    apropos -a keywords
    lolssl · 2015-09-22 16:42:57 0

  • -1
    ps aux | awk {'sum+=$3;print sum'} | tail -n 1
    tailot · 2011-07-16 16:16:59 0
  • Requires mencoder. Show Sample Output


    -1
    mencoder FILENAME.3gp -ovc lavc -lavcopts vcodec=msmpeg4v2 -oac mp3lame -lameopts vbr=3 -o FILENAME.avi
    o0110o · 2013-03-25 23:30:15 0
  • Explination: https://stackoverflow.com/questions/2257441/random-string-generation-with-upper-case-letters-and-digits/23728630#23728630 Why 16 Characters: https://www.wired.com/story/7-steps-to-password-perfection/ Show Sample Output


    -1
    python -c "import string; import random;print(''.join(random.SystemRandom().choice(string.ascii_uppercase + string.digits + string.ascii_lowercase) for _ in range(16)))"
    rootduck · 2019-06-14 17:35:12 2
  • Change :alnum: to :graph: for all printable characters Show Sample Output


    -2
    cat /dev/urandom |tr -c -d '[:alnum:]'|head -c 16;echo
    AndrewM · 2019-06-17 17:51:04 1

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See n most used commands in your bash history
You can append these commands to the bottom of the history file to access them easier with the Up key: $ sort ~/.bash_history|uniq -c|sort -n|tail -n 10|tr -s " "|cut -d' ' -f3- >> ~/.bash_history

Download all videos in your Boxee queue
Gets all videos in your boxee queue with a URL associated with them and attempts to download each using get_flash_videos

Give {Open,True}Type files reasonable names
Just a quick hack to give reasonable filenames to TrueType and OpenType fonts. I'd accumulated a big bunch of bizarrely and inconsistently named font files in my ~/.fonts directory. I wanted to copy some, but not all, of them over to my new machine, but I had no idea what many of them were. This script renames .ttf files based on the name embedded inside the font. It will also work for .otf files, but make sure you change the mv part so it gives them the proper extension. REQUIREMENTS: Bash (for extended pattern globbing), showttf (Debian has it in the fontforge-extras package), GNU grep (for context), and rev (because it's hilarious). BUGS: Well, like I said, this is a quick hack. It grew piece by piece on the command line. I only needed to do this once and spent hardly any time on it, so it's a bit goofy. For example, I find 'rev | cut -f1 | rev' pleasantly amusing --- it seems so clearly wrong, and yet it works to print the last argument. I think flexibility in expressiveness like this is part of the beauty of Unix shell scripting. One-off tasks can be be written quickly, built-up as a person is "thinking aloud" at the command line. That's why Unix is such a huge boost to productivity: it allows each person to think their own way instead of enforcing some "right way". On a tangent: One of the things I wish commandlinefu would show is the command line HISTORY of the person as they developed the script. I think it's that conversation between programmer and computer, as the pipeline is built piece-by-piece, that is the more valuable lesson than any canned script.

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Change framebuffer font
setfont load vga console font. The default font directory is usually in /lib/kbd/consolefonts. Setfont is part of kbd package. Tested on CentOS.

Re-read partition table on specified device without rebooting system (here /dev/sda).

Re-use the previous command output
The $(!!) will expand to the previous command output (by re-running the command), which becomes the parameter of the new command newcommand.

Convert wma to mp3@128k
Convert all wma to mp3@128k with ffmpeg into directory.

Determine configure options used for MySQL binary builds
Output is from Debian Lenny

convert a line to a space


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