Commands by mechmind (7)

  • It's useful mostly for your custom scripts, which running on specific host and tired on ssh'ing every time when you need one simple command (i use it for update remote apt repository, when new package have to be downloaded from another host). Don't forget to set up authorization by keys, for maximum comfort. Show Sample Output


    -3
    echo -e '#!/bin/bash\nssh remote-user@remote-host $0 "$@"' >> /usr/local/bin/ssh-rpc; chmod +x /usr/local/bin/ssh-rpc; ln -s hostname /usr/local/bin/ssh-rpc; hostname
    mechmind · 2011-12-28 17:43:34 9
  • There are a lot of commands, which invokes your player at specified time. But I prefer not to jump from by bed, when alarm start to play. Instead, this script increases volume of mpd over time, which much more pleasant when you just woke up :)


    7
    at 8:30 <<<'mpc volume 20; mpc play; for i in `seq 1 16`; do sleep 2; mpc volume +5; done'
    mechmind · 2011-11-30 17:51:27 5
  • this oneliner uses make and it's jobserver for parallel execution of your script. The '-j' flag for make defines number of subprocesses to launch, '-f' tells make use stdin instead of Makefile. Also make have neat flag '-l', which "Specifies that no new jobs (commands) should be started if there are others jobs running and the load is at least load (a floating-point number)." Also you can use plain Makefile, for better readability: targets = $(subst .png,.jpg,$(wildcard *.png)) (targets): echo convert $(subst .jpg,.png,$@) $@ all : $(targets)


    5
    echo -n 'targets = $(subst .png,.jpg,$(wildcard *.png))\n$(targets):\n convert $(subst .jpg,.png,$@) $@ \nall : $(targets)' | make -j 4 -f - all
    mechmind · 2010-07-15 07:19:17 9
  • 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 "$sudor_command"; }; alias sudor="proceed_sudo # "
    mechmind · 2010-06-29 14:56:29 6
  • For this hack you need following function: finit() { count=$#; current=1; for i in "$@" ; do echo $current $count; echo $i; current=$((current + 1)); done; } and alias: alias fnext='read cur total && echo -n "[$cur/$total] " && read' Inspired by CMake progress counters. Show Sample Output


    2
    finit "1 2 3" 3 2 1 | while fnext i ; do echo $i; done;
    mechmind · 2010-06-17 10:20:49 4
  • When you start screen as `ssh-agent screen`, agent will die after detatch. If you don't want to take care about files when stored agent's pid/socket/etc, you have to use this command.


    4
    eval `ssh-agent`; screen
    mechmind · 2010-03-07 14:58:54 4
  • With this form you dont need to cut out target directory using grep/sed/etc.


    4
    (ls; mkdir subdir; echo subdir) | xargs mv
    mechmind · 2009-11-08 11:40:55 14

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Share Your Commands


Check These Out

Lookup hostname for IP address

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Recursive grep of all c++ source under the current directory

Ask for a password, the passwd-style
You can ask repeatedly for a non-blank password using this function: function read_password() { while [ ! -n "$USER_PASSWORD" ]; do read -s -p"Password: " USER_PASSWORD if [ ! -n "$USER_PASSWORD" ]; then echo "ERROR: You must specify a valid password, please try again" fi echo done } Also you can set a time out (in seconds) to write the password read -t 10 -s -p"Password: " USER_PASSWORD_VARIABLE if [ ! $? -eq 0 ]; then echo "Time out!" fi

Given a file path, unplug the USB device on which the file is located (the file must be on an USB device !)
You have an external USB drive or key. Apply this command (using the file path of anything on your device) and it will simulate the unplug of this device. If you just want the port, just type : echo $(sudo lshw -businfo | grep -B 1 -m 1 $(df "/path/to/file" | tail -1 | awk '{print $1}' | cut -c 6-8) | head -n 1 | awk '{print $1}' | cut -c 5- | tr ":" "-")

Get a funny one-liner from www.onelinerz.net
Put this command in .bashrc and every time you open a new terminal a random quote will be downloaded and printed from onelinerz.net. By altering the URL in the w3m statement you can change the output: 1 to 10 lines - http://www.onelinerz.net/random-one-liners/(number)/ 20 newest lines - http://www.onelinerz.net/latest-one-liners/ Top 10 lines - http://www.onelinerz.net/top-100-funny-one-liners/ Top 10 lines are updated daily.

Tells the shell you are using

Find the fastest server to disable comcast's DNS hijacking
Comcast is an ISP in the United States that has started hijacking DNS requests as a "service" for its customers. For example, in Firefox, one used to be able to do a quick "I'm Feeling Lucky" Google search by typing a single word into the URL field, assuming the word is not an existing domain when surrounded by www.*.com. Comcast customers never receive the correct NX (non-existent domain) error from DNS. Instead, they are shown a page full of advertising. There is a way to "opt out" from their service, but that requires having the account password and the MAC address of your modem handy. For me, it was easier just to set static DNS servers. But the problem is, which ones to choose? That's what this command answers. It'll show you the three _non-hijacked_ Comcast DNS servers that are the shortest distance away. Perhaps you don't have Comcast (lucky you!), but hopefully this command can serve as an example of using netselect to find the fastest server from a list. Note that, although this example doesn't show it, netselect will actually perform the uniq and DNS resolution for you. Requires: netselect, curl, sort, uniq, grep

Get Cookies from bash
The loop is to compare cookies. You can remove it... Maybe you wanna use curl... $ curl www.commandlinefu.com/index.php -s0 -I | grep "Set-Cookie"

Print a random 8 digit number
Don't need to pipe the output into rs if you just tell jot to use a null separator character.


Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for: