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 5
  • 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 1
  • 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 1
  • 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 "$sudor_command"; }; alias sudor="proceed_sudo # "
    mechmind · 2010-06-29 14:56:29 0
  • For this hack you need following function: finit() { count=$#; 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 0
  • 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 0
  • 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 5

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Remove a range of lines from a file

a simple bash one-liner to create php file and call php function

list ips with high number of connections

Check if a command is available in your system
Usefull to detect if a commad that your script relies upon is properly installed in your box, you can use it as a function function is_program_installed() { type "$1" >/dev/null } Invoke it and check the execution code is_program_installed "dialog" if [ ! $? -eq 0 ]; then echo "dialog is not installed" exit 1 fi

Remove sound from video file using mencoder
Remove sound from input video file, output video stream is copied from input video stream, with no audio.

Backup VPS disk to another host

find all writable (by user) files in a directory tree (use 4 for readable, 1 for executable)

List your installed Chromium extensions (with url to each page)
Gives you a list for all installed chrome (chromium) extensions with URL to the page of the extension. With this you can easy add a new Bookmark folder called "extensions" add every URL to that folder, so it will be synced and you can access the names from every computer you are logged in. ------------------------------------------------------------------------------------------------------------------ Only tested with chromium, for chrome you maybe have to change the find $PATH.

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

Create a new file


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