Commands by mulad (10)

  • FreeBSD version of the Linux command mount discimg.iso /cdrom -o loop The "mdconfig" command creates a device and prints the name (typically "md0"). Just append that to "/dev/" and mount. Once unmounted, you can unconfigure the device with mdconfig -d -u 0 using "0" for md0, "1" for md1, etc.


    -1
    mount -t cd9660 /dev/`mdconfig -a -t vnode -f discimg.iso` /cdrom
    mulad · 2009-02-19 06:31:14 0
  • Many sites with Flash video players will download video files to /tmp on Linux, with temporary filenames like "FlashbGTHm4". These will often play in mplayer, totem, or other movie playing software. You must first navigate to a video page, let it start loading, and then pause playback.


    1
    mplayer $(ls -t /tmp/Flash*|head -1)
    mulad · 2009-02-19 04:38:40 3
  • If your CVS server has moved, here's a way to update your CVS Root files throughout your code tree without checking out a new copy of your files.


    0
    find cvsdir -name Root -exec sed -i 's/oldserver/newserver/' {} \;
    mulad · 2009-02-19 04:31:13 0
  • An apt-get wrapper function which will run the command via sudo, but will run it normally if you're only downloading source files. This was a bit of an excuse to show off the framework of cmd && echo true || echo false ...but as you can see, you must be careful about what is in the "true" block to make sure it executes without error, otherwise the "false" block will be executed. To allow the apt-get return code to pass through, you need to use a more normal if/else block: apt-get () { if [ "$1" = source ]; then command apt-get "[email protected]"; else sudo apt-get "[email protected]"; fi }


    1
    apt-get () { [ "$1" = source ] && (command apt-get "[email protected]";true) || sudo apt-get "[email protected]" }
    mulad · 2009-02-19 04:17:24 1
  • These days, most software distributed in tar files will just contain a directory at the top level, but some tar files don't have this and can leave you with a mess of files in the current folder if you blindly execute tar zxvf something.tar.gz This command can help you clean up after such a mistake. However, note that this has the potential to do bad things if someone has been *really* nasty with filenames.


    2
    tar ztf tar-lacking-subdirectory.tar.gz | xargs rm
    mulad · 2009-02-19 00:34:09 1
  • The "vorbiscomment" utility lets you update information such as artist names and song and album tags in an Ogg Vorbis file. You can use this command to fix any mistakes that were made when ripping an album.


    1
    for f in *.ogg; do vorbiscomment -l "$f" | sed 's/peter gabriel/Peter Gabriel/' | vorbiscomment -w "$f"; done
    mulad · 2009-02-18 23:54:01 0
  • Yet another ps grep function, but this one includes the column headings. Show Sample Output


    1
    psg () { ps auxwww | egrep "$1|PID" | grep -v grep }
    mulad · 2009-02-18 23:37:35 0
  • The $[...] block in bash and zsh will let you do math. echo $[6*7] This is the same as using $((...)), which also works in ksh. Of course, this is a simple, dumb wrapper and doesn't allow floating-point. Show Sample Output


    0
    while true; do read i; echo $[$i]; done
    mulad · 2009-02-18 23:13:09 2
  • Upgraded Debian/Ubuntu/etc. systems may have a number of "orphaned" packages which are just taking up space, which can be found with the "deborphan" command. While you could just do "dpkg --purge $(deborphan)", the act of purging orphans will often create more orphans. This command will get them all in one shot.


    6
    while [ $(deborphan | wc -l) -gt 0 ]; do dpkg --purge $(deborphan); done
    mulad · 2009-02-18 22:31:22 0
  • This will convert filenames from uppercase to lowercase. I find this useful after downloading images from my digital camera. This works for English, but other languages may need something slightly more complex like this: for i in *; do mv "$i" "$(echo $i|tr [:upper:] [:lower:])"; done Also, the quote marks aren't necessary if your filenames don't contain spaces.


    5
    for i in *; do mv "$i" "$(echo $i|tr A-Z a-z)"; done
    mulad · 2009-02-18 21:29:28 1

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monitor a tail -f command with multiple processes
when using named pipes only one reader is given the output by default. Also, most commands piped to by grep use a buffer which save output until tail -f finishes, which is not convenient. Here, using a combination of tee, sub-processes and the --line-buffered switch in grep we can workaround the problem.

Merge video files together using mencoder (part of mplayer)
Using mplayer's mencoder, you can merge video files together. '-oac' specifies the audio encoding (here copy, to just copy and not compress) '-ovc' specifies the video encoding (same thing).

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"

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"

Setting global redirection of STDERR to STDOUT in a script
You have a script where =ALL= STDERR should be redirected to STDIN and you don't want to add "2>&1" at the end of each command... E.G.: $ ls -al /foo/bar 2>&1 Than just add this piece of code at the beginning of your script! I hope this can help someone. :)

change dinosaur poop into gold
if firefox is running the database is locked, so you need to copy the places.sqlite file temporarily somewhere to be able to query it...

Hide or show Desktop Icons on MacOS
Hides all Files and Folders on the MacOS Desktop. To show files and folders, type "true" instead of "false". "Finder" at the end is case sensitive, "finder" doesn’t work

Show apps that use internet connection at the moment.
show only the name of the apps that are using internet

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

suspend to ram without root
$dbus-send --system --print-reply --dest="org.freedesktop.UPower" /org/freedesktop/UPower org.freedesktop.UPower.Suspend


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