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Generate a ZenCart-style MD5 password hash.
ZenCart uses a MD5 with a salt to secure its passwords. If you need to forcibly change someone's password to a known value within the database, this one-liner can generate the password. Change the value of 'p' to the password you want.

list all file-types (case-insensitive extensions) including subdirectories

Display the definition of a shell function
Display the code of a previously defined shell function.

rot13 simple substitution cipher via command line
E.g. Useful for hiding spoilers in reviews, etc.

create random numbers within range for conjob usage
if you need to install cron jobs in a given time range.

Installing debian on fedora (chrooted)

Iterate through current directory + all subs for C++ header files and rank by # of comments
This shows you which files are most in need of commenting (one line of output per file)

Determine space taken by files of certain type
Just how much space are those zillions of database logs taking up ? How much will you gain on a compression rate of say 80% ? This little line gives you a good start for your calculations.

View All Processess Cmdlines and Environments
Grabs the cmdline used to execute the process, and the environment that the process is being run under. This is much different than the 'env' command, which only lists the environment for the shell. This is very useful (to me at least) to debug various processes on my server. For example, this lets me see the environment that my apache, mysqld, bind, and other server processes have. Here's a function I use: $ aa_ps_all () { ( cd /proc && command ps -A -opid= | xargs -I'{}' sh -c 'test $PPID -ne {}&&test -r {}/cmdline&&echo -e "\n[{}]"&&tr -s "\000" " "

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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