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Recursive chmod all files and directories within the current directory

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

a function to create a box of '=' characters around a given string.
First argument: string to put a box around. Second argument: character to use for box (default is '=') Same as command #4962, cleaned up, shortened, and more efficient. Now a ' * ' can be used as the box character, and the variables get unset so they don't mess with anything else you might have. They marked c++ as a function for this command, but I'm not sure why. Must be a bug.

detect the fastest ldap server on a intranet
This command line detect ldap hosts, by mandatory dns entry, then ping them to detect response average. based on ping response average it sorts and print the faster server in first output line

add repeated watermark to image

split a multi-page PDF into separate files
Have to do this once per output file, because if device is 'pdfwrite', even if 'gs' sees '%d' in the OutputFile it still only creates one single output file. Embed it into a simple shell script if you want to split a document out into one file for every page.

Runs a command without hangups.
puts command in background and sends its output to nohup.out file it will not die if you log out fromyour shell session ;-)

Emulating netcat -e (netcat-traditional or netcat-openbsd) with the gnu-netcat
Then just nc servername 2600 and ./script.sh kill the client with ctrl+c. You can reconnect several times. kill the server with exit

Grab a list of MP3s out of Firefox's cache
Grab a list of MP3s (with full path) out of Firefox's cache Ever gone to a site that has an MP3 embedded into a pesky flash player, but no download link? Well, this one-liner will yank the *full path* of those tunes straight out of FF's cache in a clean list. Shorter and Intuitive version of the command submitted by (TuxOtaku)

Numeric zero padding file rename
This uses Perl's rename utility (you may have to call it as prename on your box) and won't choke on spaces or other characters in filenames. It will also zero pad a number even in filenames like "vacation-4.jpg".


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