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.

    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.

    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.

    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 }

    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.

    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.

    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

    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

    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.

    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.

    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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Edit a file on a remote host using vim

Reconnect to screen without disconnecting other sessions
Have your screen session running in multiple places. (warning, things start to look weird if the terminal windows have different dimensions)

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

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Generate an XKCD #936 style 4 word password
4 random words are better than one obfuscated word

find and grep Word docs
Find Word docs by filename in the current directory, convert each of them to plain text using antiword (taking care of spaces in filenames), then grep for a search term in the particular file. (Of course, it's better to save your data as plain text to make for easier grepping, but that's not always possible.) Requires antiword. Or you can modify it to use catdoc instead.

list block devices
Shows all block devices in a tree with descruptions of what they are.

Erase CD RW

Displays an animated hourglass for x amount of seconds

drop first column of output by piping to this

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