Commands using echo (1,523)

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print shared library dependencies
May be used on (embedded) systems lack ldd

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"

reverse order of file
awk reverse order of lines (emulates "tac")

A function to find the newest file in a directory

guitar synthesizer in one line of C
outputs a f=220Hz guitar string sound (fifth string A) needs ALSA

Stat each file in a directory
This will run stat on each file in the directory.

Quick searching with less

Keep a copy of the raw Youtube FLV,MP4,etc stored in /tmp/
Certain Flash video players (e.g. Youtube) write their video streams to disk in /tmp/ , but the files are unlinked. i.e. the player creates the file and then immediately deletes the filename (unlinking files in this way makes it hard to find them, and/or ensures their cleanup if the browser or plugin should crash etc.) But as long as the flash plugin's process runs, a file descriptor remains in its /proc/ hierarchy, from which we (and the player) still have access to the file. The method above worked nicely for me when I had 50 tabs open with Youtube videos and didn't want to have to re-download them all with some tool.

add static arp entry to default gateway, arp poison protection

Return threads count of a process
Source: http://superuser.com/questions/49408/how-do-i-monitor-or-view-the-thread-count-of-a-certain-process-on-aix


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