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Find non ascii characters in files in folder

autossh + ssh + screen = super rad perma-sessions
Only useful for really flakey connections (but im stuck with one for now). Though if youre in this situation ive found this to be a good way to run autossh and it does a pretty good job of detecting when the session is down and restarting. Combined with the -t and screen commands this pops you back into your working session lickety split w/ as few headaches as possible. And if autossh is a bit slow at detecting the downed ssh connection, just run this in another tab/terminal window to notify autossh that it should drop it and start over. Basically for when polling is too slow. kill -SIGUSR1 `pgrep autossh`

create a progress bar...
A simple way yo do a progress bar like wget.

Check whether laptop is running on battery or cable
The original proc file doesn't exist on my system.

Get all IPs via ifconfig
The initial version of this command also outputted extra empty lines, so it went like this: 192.168.166.48 127.0.0.1 This happened on Ubuntu, i haven't tested on anything else.

Perl Simple Webserver
First we accept a socket and fork the server. Then we overload the new socket as a code ref. This code ref takes one argument, another code ref, which is used as a callback. The callback is called once for every line read on the socket. The line is put into $_ and the socket itself is passed in to the callback. Our callback is scanning the line in $_ for an HTTP GET request. If one is found it parses the file name into $1. Then we use $1 to create an new IO::All file object... with a twist. If the file is executable("-x"), then we create a piped command as our IO::All object. This somewhat approximates CGI support. Whatever the resulting object is, we direct the contents back at our socket which is in $_[0].

Find unused IPs on a given subnet
Somewhat shorter version.

Show latest changed files

Sort the size usage of a directory tree by gigabytes, kilobytes, megabytes, then bytes.
Probably only works with GNU du and modern perls.

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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