Commands using cat (508)

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Convert a SVG file to grayscale
It requires inkscape 0.46 and lxml packages

Runs previous command replacing foo by bar every time that foo appears
Very useful for rerunning a long command changing some arguments globally. As opposed to ^foo^bar, which only replaces the first occurrence of foo, this one changes every occurrence.

Run the Firefox Profile Manager
even when another instance is already open. Great for testing purposes when you need to be 2 people at once on the same site.

check open ports without netstat or lsof

Check a server is up. If it isn't mail me.
Joker wants an email if the Brand X server is down. Set a cron job for every 5 mins with this line and he gets an email when/if a ping takes longer than 3 seconds.

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

Find the package that installed a command

NICs, IPs, and Mac
Needed to get the Mac of various devices on a solaris box, but didn't have root. This command used awk to display the Network device, the IP, and the MAC a line at a time.

find text in a file
this will find text in the directory you specify and give you line where it appears.

convert single digit to double digits
works only in zsh, requires autoload zmv


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