Commands by unixmonkey15302 (1)

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List open files that have no links to them on the filesystem
I have come across a situation in the past where someone has unlinked a file by running an 'rm' command against it while it was still being written to by a running process. The problem manifested itself when a 'df' command showed a filesystem at 100%, but this did not match the total value of a 'du -sk *'. When this happens, the process continues to write to the file but you can no longer see the file on the filesystem. Stopping and starting the process will, more often than not, get rid of the unlinked file, however this is not always possible on a live server. When you are in this situation you can use the 'lsof' command above to get the PID of the process that owns the file (in the sample output this is 23521). Run the following command to see a sym-link to the file (marked as deleted): $ cd /proc/23521/fd && ls -l Truncate the sym-link to regain your disk space: $ > /proc/23521/fd/3 I should point out that this is pretty brutal and *could* potentially destabilise your system depending on what process the file belongs to that you are truncating.

Find the package that installed a command

Find broken symlinks and delete them
If you don't want to delete them, but just want to list them, do $ find -L /path -type l If you want to delete them with confirmation first, do $ find -L /path -type l -exec rm -i {} + Using the -L flag follows symlinks, so the -type l test only returns true if the link can't be followed, or is a symlink to another broken symlink.

Displays the current time using HTTP
This command will show the current GMT time using HTTP. This might be useful if you just want to know what's the current human-readable and accurate-enough time, without changing the system time, using a simple command that would work regardless of the availability of NTP. Note: To get a quicker and more accurate response, replace google.com with your local NTP server. Also can be used as an alternative to the "htpdate" program: http://www.commandlinefu.com/commands/view/668/set-your-computers-clock-using-http-and-htp-http-time-protocol-when-ntpsntp-is-not-available

Create test images
Useful to test programs and webpages.

Quick and dirty RSS
runs an rss feed through sed replacing the closing tags with newlines and the opening tags with white space making it readable.

Donwload media from *.rm from an url of type htttp://.../*.ram

Find the package that installed a command

Lists all usernames in alphabetical order
Save some CPU, and some PIDs. :)

List NYC startups that are hiring


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