Commands by matrixguy (1)

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Delete line number 10 from file
Very useful when the ssh key of a host has changed and ssh refuses to connect to the machine, while giving you the line number that has changed in ~/.ssh/known_hosts.

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

Equivalent to ifconfig -a in HPUX

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

sshfs usage
you can use this command for mounting local directory to a remost directory..

List Threads by Pid along with Thread Start Time
This command will list all threads started by a particular pid along with the start time of each thread. This is very valuable when diagnosing thread leaks.

Optimal way of deleting huge numbers of files
Optimal way of deleting huge numbers of files Using -delete is faster than: $ find /path/to/dir -type f -print0 | xargs -0 rm $ find /path/to/dir -type f -exec rm {} + $ find /path/to/dir -type f -exec rm \-f {} \;

Keep from having to adjust your volume constantly
Run this in the directory you store your music in. mp3gain and vorbisgain applies the ReplayGain normalization routine to mp3 and ogg files (respectively) in a reversible way. ReplayGain uses psychoacoustic analysis to make all files sound about the same loudness, so you don't get knocked out of your chair by loud songs after cranking up the volume on quieter ones.

Get the list of local files that changed since their last upload in an S3 bucket
Can be useful to granulary flush files in a CDN after they've been changed in the S3 bucket.

bash shortcut: !$ !^ !* !:3 !:h and !:t
When expanding, bash output the command, so don't be affraid if you type the command. Here is the details: First examples: $echo foo bar foobar barfoo First argument: $echo !$ echo barfoo barfoo (Note that typing echo foo bar foobar barfoo && echo !$, bash substitute !$ with $:1) Last argument: $echo foo bar foobar barfoo && echo !^ echo foo bar foobar barfoo && echo barfoo foo bar foobar barfoo barfoo All the arguments: $echo !* echo foo bar foobar barfoo foo bar foobar barfoo The third argument: $echo foo bar foobar barfoo && echo !:3 echo foo bar foobar barfoo && echo foobar foo bar foobar barfoo foobar You may want to add {} for large numbers: echo !:{11} for example Now with path: $echo /usr/bin/foobar /usr/bin/foobar For the head: $echo !$:h echo /usr/bin /usr/bin And the tail: $echo !$:t echo foobar foobar You also may want to try !:h and !:t or !!3-4 for the third and the fourth (so !!:* == !!:1-$)


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