Commands by kaleksandrov (2)

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Remove newlines from output
Remove newlines from output. One character shorter than awk /./ filename and doesn't use a superfluous cat. To be fair though, I'm pretty sure fraktil was thinking being able to nuke newlines from any command is much more useful than just from one file.

Extend a logical volume to use up all the free space in a volume group

vimdiff local and remote files via ssh
Lifted from http://linux.spiney.org/remote_diff_with_vim_and_ssh which points out credits for the inspiration.

Relocate a file or directory, but keep it accessible on the old location throug a simlink.
Used for moving stuff around on a fileserver

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

check open ports (both ipv4 and ipv6)
While `lsof` will work, why not use the tool designed explicitly for this job? (If not run as root, you will only see the names of PID you own)

list folders containing less than 2 MB of data
This command will search all subfolders of the current directory and list the names of the folders which contain less than 2 MB of data. I use it to clean up my mp3 archive and to delete the found folders pipe the output to a textfile & run: $ while read -r line; do rm -Rv "$line"; done < textfile

Batch rename extension of all files in a folder, in the example from .txt to .md
Batch rename extension of all files in a folder, in the example from .txt to .md mmv most likely must be installed, but is very powerfull when you want to move/copy/append/link multiple files by wildcard patterns.

Create a 5 MB blank file via a seek hole
Similar to the original, but is much faster since it only needs to write the last byte as zero. A diff on testfile and testfile.seek will return that they are the same.

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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