Commands by unixmonkey7109 (11)

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Create a mirror of a local folder, on a remote server
Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)

Printing multiple years with Unix cal command
print multiple increasing years using cal - calendar -. You can also try $seq Start Increment End

diff two sorted files
Sees if two records differ in their entries, irrespective of order.

scroll file one line at a time (w/only UNIX base utilities)
usage examples ls largedir |rd lynx -dump largewebsite.com |rd rd < largelogfile

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].

list all file extensions in a directory
A shorter version

Git Global search and replace
Find all the occurrences in the git repo of 'foo' and replace with 'bar'

What is my ip?

Display a Lissajous curve in text
Use Ruby's standard Curses module to display a Lissajous curve in the console. Replace the "0.2" with different numbers for different curves.

Find out how old a web page is
I used to use the Firefox "View page info" feature a lot to determine how stale the web page I was looking at was. Now that I use mostly Chrome I miss that feature, so here is a command line alternative using wget. The -S says to display the server response, the --spider says to not download any files/pages, just fetch the header. The output goes to stderr, so to grep it you use 2>&1 to combine the stderr stream with stdout, the pipe that to grep for Last-Modified. You can use curl instead if you have it installed, like this: $ curl --head -s http://osswin.sourceforge.net | grep Mod


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