Commands tagged command (17)

  • 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 0
  • 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 1
  • 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 1
  • * 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 0
  • 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
  • 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

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add all files not under version control to repository
With the force options the same results can be achieved

Recursive find and replace file extension / suffix (mass rename files)
Find recursively all files in ~/Notes with the extension '.md' and pipe that via xargs to rename command, which will replace every '.md' to '.txt' in this example (existing files will not be overwritten).

ZSH prompt. ':)' after program execution with no error, ':(' after failure.
sorry for my english

Recursively lists all files in the current directory, except the ones in '.snapshot' directory
This can be useful for those who have mounted NetApp file-systems with snapshot activated.

Quickly display a string as Qr Code
Takes the first argument (string) and display a Qr code version of that.

Url Encode
This one uses hex conversion to do the converting and is in shell/sed only (should probably still use the python/perl version).

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"

Stop Flash from tracking everything you do.
Brute force way to block all LSO cookies on a Linux system with the non-free Flash browser plugin. Works just fine for my needs. Enjoy.

Simple Video Surveillance by email
This takes a picture (with the web cam) every 5 minutes, and send the picture to your e-mail. Some systems support mail -a "References: " so that all video surveillance emails are grouped in a single email thread. To keep your inbox clean, it is still possible to filter and move to trash video surveillance emails (and restore these emails only if you really get robbed!) For instance with Gmail, emails sent to me+trash@gmail.com can be filtered with "Matches: DeliveredTo:me+trash@gmail.com"

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


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