Commands by Lewix (1)

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Use a var with more text only if it exists
See "Parameter Expansion" in the bash manpage. They refer to this as "Use Alternate Value", but we're including the var in the at alternative.

send a circular

play audio stream and video stream in two different mplayer instances
Sometimes audio and video are not sync'ed. The factor 1.0884 is the quotient 48000/44100. One mplayer plays the audio file in the background, the other the video in the foreground. You can dump the audio file before with another commandlinefu

Clean up display when the bash prompt is displayed
This will cause bash to fix a garbled terminal before the prompt is printed. For example, if you cat a file with nonprintable character sequences, the terminal sometimes ends up in a mode where it only prints line drawing characters. This sequence will return the terminal to the standard character set after every command.

reclaim your window titlebars (in ubuntu lucid)

Release memory used by the Linux kernel on caches
The Linux kernel uses unused memory in caches. When you execute "free" you never get the "real" available memory.

list files recursively by size

List folders containing only PNGs

Rename files in batch

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"


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