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Dumping Audio stream from flv (using mplayer)

Show top SVN committers for the last month

Runs a command without hangups.
puts command in background and sends its output to nohup.out file it will not die if you log out fromyour shell session ;-)

Find the package that installed a command

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"

Get the number of days in a given month and year

Url Encode
Converts reserved characters in a URI to their percent encoded counterparts. Alternate python version: $ echo "$url" | python -c 'import sys,urllib;print urllib.quote(sys.stdin.read().strip())'

Advanced python tracing
Trace python statement execution and syscalls invoked during that simultaneously

Swap the two last arguments of the current command line
Say you just typed a long command like this: $ rsync -navupogz --delete /long/path/to/dir_a /very/long/path/to/dir_b but you really want to sync dir_b to dir_a. Instead of rewriting all the command line, just type followed by , and your command line will read $ rsync -navupogz --delete /very/long/path/to/dir_b /long/path/to/dir_a

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.


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