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Match a URL
For the record: I didn't build this. Just shared what I found that worked. Apologies to the original author! I decided I should fix the case where http://example.com is not matched for the next time I need this. So I read rfc1035 and formalized the host name regex. If anyone finds any more holes, please comment.

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

Selecting a random file/folder of a folder
Also looks in subfolders

Convert all files for iPhone with HandbrakeCLI

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"

txt2html
Convert Text to HTML

Add fade in/out to first & last 25 frames of a video
Replace vid.mp4 with the path to your original video file, and out.mp4 to the path where you want to save the new file. To view the output first before saving, remove "-consumer avformat:out.mp4" from the end. Documentation for mlt framework and melt command can be found here: http://www.mltframework.org/bin/view/MLT/Documentation

print offsets of file disk for losetup/loop-mount
If you want to mount partitions of an disk image, you need the offsets and sizes of the partitions. This command prints them in the format that losetup understands.

copy timestamps of files from one location to another - useful when file contents are already synced but timestamps are wrong.
Sometimes when copying files from one place to another, the timestamps get lost. Maybe you forgot to add a flag to preserve timestamps in your copy command. You're sure the files are exactly the same in both locations, but the timestamps of the files in the new home are wrong and you need them to match the source. Using this command, you will get a shell script (/tmp/retime.sh) than you can move to the new location and just execute - it will change the timestamps on all the files and directories to their previous values. Make sure you're in the right directory when you launch it, otherwise all the touch commands will create new zero-length files with those names. Since find's output includes "." it will also change the timestamp of the current directory. Ideally rsync would be the way to handle this - since it only sends changes by default, there would be relatively little network traffic resulting. But rsync has to read the entire file contents on both sides to be sure no bytes have changed, potentially causing a huge amount of local disk I/O on each side. This could be a problem if your files are large. My approach avoids all the comparison I/O. I've seen comments that rsync with the "--size-only" and "--times" options should do this also, but it didn't seem to do what I wanted in my test. With my approach you can review/edit the output commands before running them, so you can tell exactly what will happen. The "tee" command both displays the output on the screen for your review, AND saves it to the file /tmp/retime.sh. Credit: got this idea from Stone's answer at http://serverfault.com/questions/344731/rsync-copying-over-timestamps-only?rq=1, and combined it into one line.

drop first column of output by piping to this


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