Commands by warlock (1)

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"I Feel Lucky" for Google Images
prompts for a search term and then pulls down the first result from google images

How to trim a video using ffmpeg
Will trim the video to 4 seconds starting from the beginning. The -vcodec , -acodec options are required so that ffmpeg knows in what video/audio format you want for the new video.

Rename files in batch

Generate soothing noise
Substitute 'brown' with 'pink' or 'white' according to your taste. I put this on my headphones when I'm working in an "open concept" office, where there are always three to five conversations going in earshot, or if I'm working somewhere it is "rude" of me to tell a person to turn off their cubicle radio.

rsync over ssh using alternative port number
Useful, when you need to backup/copy/sync a folder over ssh with a non standard port number

Function that outputs dots every second until command completes
Very useful in shell scripts because you can run a task nicely in the background using job-control and output progress until it completes. Here's an example of how I use it in backup scripts to run gpg in the background to encrypt an archive file (which I create in this same way). $! is the process ID of the last run command, which is saved here as the variable PI, then sleeper is called with the process id of the gpg task (PI), and sleeper is also specified to output : instead of the default . every 3 seconds instead of the default 1. So a shorter version would be sleeper $!; The wait is also used here, though it may not be needed on your system. $ echo ">>> ENCRYPTING SQL BACKUP" $ gpg --output archive.tgz.asc --encrypt archive.tgz 1>/dev/null & $ PI=$!; sleeper $PI ":" 3; wait $PI && rm archive.tgz &>/dev/null Previously to get around the $! not always being available, I would instead check for the existance of the process ID by checking if the directory /proc/$PID existed, but not everyone uses proc anymore. That version is currently the one at http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html but I plan on upgrading to this new version soon.

list block level layout

Know SELinux status
Usefule to check whether SELinux is in force or disabled. Though you need to be superuser while execute this command.

Delete all flash cookies.
Maybe you want first check which files will be deleted: $ find $HOME -name '*.sol' -exec echo rm {} \;

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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