Commands by longdrink (2)

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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"

Turning off display
To turn off monitor: xset dpms force off To turn on, simply press a key, or move mouse/mousepad.

sed : using colons as separators instead of forward slashes
Having to escape forwardslashes when using sed can be a pain. However, it's possible to instead of using / as the separator to use : . I found this by trying to substitute $PWD into my pattern, like so $ sed "s/~.*/$PWD/" file.txt Of course, $PWD will expand to a character string that begins with a / , which will make sed spit out an error such as "sed: -e expression #1, char 8: unknown option to `s'". So simply changing it to $ sed "s:~.*:$PWD:" file.txt did the trick.

Count the number of pages of all PDFs in current directory and all subdirs, recursively

Ignore a directory in SVN, permanently
This command allow you to ignore certain directories on SVN commands, like SVN STATUS. It is sad see a lot of temporary files from templates_c for each "svn status", no? ;-) This works only on directories under revision control.

Lock the hardware eject button of the cdrom
This command will lock the hardware eject button of your cdrom drive. Some uses are: 1: If you have a toddler and has discovered the cdrom button 2: If you are carrying a laptop in a bag or case and don't want it to eject if the button is inadvertently pressed. To unlock the button use: $ eject -i 0

easy C shell math calculators
allows simple C shell access to the power of bc - never could figure out how to do the same thing with Bash - that's why I use tcsh most of the time.

Attempt an XSS exploit on commandlinefu.com
Mouse around the title of this item, and note that your cookies are being logged to the console. If I were evil, I could instead send everyone's cookies to my site, and then post up-votes on all my submissions using their cookies, and try to delete every other submission, until clfu was completely pwned by me, redirecting people to malware and porn sites, and so on. Update - now fixed.

Silently ensures that a FS is mounted on the given mount point (checks if it's OK, otherwise unmount, create dir and mount)
In my example, the mount point is /media/mpdr1 and the FS is /dev/sdd1 /mountpoint-path = /media/mpdr1 filesystem=/dev/sdd1 Why this command ? Well, in fact, with some external devices I used to face some issues : during data transfer from the device to the internal drive, some errors occurred and the device was unmounted and remounted again in a different folder. In such situations, the command mountpoint gave a positive result even if the FS wasn't properly mounted, that's why I added the df part. And if the device is not properly mounted, the command tries to unmount, to create the folder (if it exists already it will also work) and finally mount the FS on the given mount point.

c_rehash replacement
When you don't have c_rehash handy. Really simple - if you have a .pem file that doesn't really contain a x509 cert (let's say, newreq.pem), it will create a link, simply called '.0', pointing to that file.


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