Commands using file (166)

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Count the total amount of hours of your music collection
First the find command finds all files in your current directory (.). This is piped to xargs to be able to run the next shell pipeline in parallel. The xargs -P argument specifies how many processes you want to run in parallel, you can set this higher than your core count as the duration reading is mainly IO bound. The -print0 and -0 arguments of find and xargs respectively are used to easily handle files with spaces or other special characters. A subshell is executed by xargs to have a shell pipeline for each file that is found by find. This pipeline extracts the duration and converts it to a format easily parsed by awk. ffmpeg reads the file and prints a lot of information about it, grep extracts the duration line. cut and sed cut out the time information, and tr converts the last . to a : to make it easier to split by awk. awk is a specialized programming language for use in shell scripts. Here we use it to split the time elements in 4 variables and add them up.

Matrix Style
Same as above but slooooow it down

Watch movies in your terminal
requires mplayer

Press a key automatically
Press a key automatically via xvkbd.

list files recursively by size

sends your internal IP by email
This is useful if you have need to do port forwarding and your router doesn't assign static IPs, you can add it to a script in a cron job that checks if you IP as recently changed or with a trigger script. This was tested on Mac OSX.

Pipe text from shell to windows cut and paste buffer using PuTTY and XMing.
Set up X forwarding in PuTTY, with X display location set to :0.0 Launch PuTTY ssh session. Launch Xming. Make sure that display is set to :0.0 (this is default). $ echo "I'm going to paste this into WINDERS XP" | xsel -i will insert the string into the windows cut and paste buffer. Thanks to Dennis Williamson at stackoverflow.com for sharing...

Stripping ^M at end of each line for files
just deletes to rogue CR from dos files, and tr is always available.

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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