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Make directories for and mount all iso files in a folder

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.

Smart `cd`.. cd to the file directory if you try to cd to a file
This little function will smarten 'cd'. If you try to cd into a file (which I guess we all have done), it cd's into the directory of that file instead. I had to use nesten if's, to get cd to still work with 'cd' (to get to $HOME), 'cd -' (to get to last directory), and 'cd foo\ bar'.

Generate a random password 30 characters long
According to the gpg(1) manual: --gen-random 0|1|2 count Emit count random bytes of the given quality level 0, 1 or 2. If count is not given or zero, an endless sequence of random bytes will be emitted. If used with --armor the output will be base64 encoded. PLEASE, don't use this command unless you know what you are doing; it may remove precious entropy from the system! If your entropy pool is critical for various operations on your system, then using this command is not recommended to generate a secure password. With that said, regenerating entropy is as simple as: $ du -s / This is a quick way to generate a strong, base64 encoded, secure password of arbitrary length, using your entropy pool (example above shows a 30-character long password).

Backup with versioning
Apart from an exact copy of your recent contents, also keep all earlier versions of files and folders that were modified or deleted. Inspired by EVACopy http://evacopy.sourceforge.net

Check reverse DNS
The +short option should make dig less chatty.

Show directories in the PATH, one per line
This version uses Pipes, but is easier for the common user to grasp... instead of using sed or some other more complicated method, it uses the tr command

lsof equivalent on solaris
Report fstat(2) and fcntl(2) information for all open files in each process.

setup a tunnel from destination machine port 80 to localhost 2001, via a second (hub) machine.
this is handy when the hubmachine is the only machine that can connect to the destination machine (allowed on ip by firewall) and you want to access it from your laptop.

Summarise the size of all files matching a simple regex
Use the find command to match certain files and summarise their total size in KBytes.


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