Commands using perl (369)

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Generate a list of installed packages on Debian-based systems
This command is useful when you want to install the same packages on another fresh OS install for example. To do that, use: $ sudo dpkg --set-selections < LIST_FILE

defragment files
Thanks to flatcap for optimizing this command. This command takes advantage of the ext4 filesystem's resistance to fragmentation. By using this command, files that were previously fragmented will be copied / deleted / pasted essentially giving the filesystem another chance at saving the file contiguously. ( unlike FAT / NTFS, the *nix filesystem always try to save a file without fragmenting it ) My command only effects the home directory and only those files with your R/W (read / write ) permissions. There are two issues with this command: 1. it really won't help, it works, but linux doesn't suffer much (if any ) fragmentation and even fragmented files have fast I/O 2. it doesn't discriminate between fragmented and non-fragmented files, so a large ~/ directory with no fragments will take almost as long as an equally sized fragmented ~/ directory The benefits i managed to work into the command: 1. it only defragments files under 16mb, because a large file with fragments isn't as noticeable as a small file that's fragmented, and copy/ delete/ paste of large files would take too long 2. it gives a nice countdown in the terminal so you know how far how much progress is being made and just like other defragmenters you can stop at any time ( use ctrl+c ) 3. fast! i can defrag my ~/ directory in 11 seconds thanks to the ramdrive powering the command's temporary storage bottom line: 1. its only an experiment, safe ( i've used it several times for testing ), but probably not very effective ( unless you somehow have a fragmentation problem on linux ). might be a placebo for recent windows converts looking for a defrag utility on linux and won't accept no for an answer 2. it's my first commandlinefu command

move cursor to beginning of command line
Pressing Ctrl combined with 'a' will move the cursor to the beginning of the command under bash (other shells?). I used to do this after arrowing up for the last command, then typing 'sudo ' to run the last command as root, but of course the all time greatest command here `sudo !!` is more succinct. Still Ctrl+A can be very useful when you want to edit something at/close to the beginning of the command line.

Rotate a set of photos matching their EXIF data.
You need jhead package.

Select and Edit a File in the Current Directory
This command displays a simple menu of file names in the current directory. After the user made a choice, the command invokes the default editor to edit that file. * Without the break statement, the select command will loop forever * Setting the PS3 prompt is optional * If the user types an invalid choice (such as the letter q), then the variable $f will become an empty string. * For more information, look up the bash's select command

Gets the english pronunciation of a phrase
Usage examples: say hello say "hello world" say hello+world

list block devices
Shows all block devices in a tree with descruptions of what they are.

youtube2m3u
generate playlists from youtube ( or othre things that support yt-dlp)

How long has this disk been powered on

PulseAudio: set the volume via command line
If you have more than one SINK


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