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Retrieve "last modified" timestamp of web resource in UTC seconds
This command line assumes that "${url}" is the URL of the web resource. It can be useful to check the "freshness" of a download URL before a GET request.

Edit the list of to ignore files in the active directory
Standard command, but I always have to search for it... ;-)

Decode base64-encoded file in one line of Perl
If you are in an environment where you don't have the base64 executable or MIME tools available, this can be very handy for salvaging email attachments when the headers are mangled but the encoded document itself is intact.

Download all Red Hat Manuals - A better way by user Flatcap
Let's give Flatcap credit for this elegant solution, instead of leaving it hidden as a comment. Tested on RHEL6 and it works. Nice and clean.

Debian Runlevel configuration tool
This tool configures system services in connection with system runlevels. It turns on/off services using the scripts in /etc/init.d/. Rcconf works with System-V style runlevel configuration. It is a TUI(Text User Interface) frontend to the update-rc.d command.

See non printable caracters like tabulations, CRLF, LF line terminators ( colored )
For fancier and cleaner output, try the following snippet : $ showendlines(){ while read i; do od --address-radix=n --width=$(wc -c

Kill a broken ssh connection
This is useful for example if you are on ssh in a server and the server goes down without letting you out. This is part of a larget sets of escape sequences provided by ssh. You can find them with ~? Here's the list: ~. - terminate connection (and any multiplexed sessions) ~B - send a BREAK to the remote system ~C - open a command line ~R - request rekey ~V/v - decrease/increase verbosity (LogLevel) ~^Z - suspend ssh ~# - list forwarded connections ~& - background ssh (when waiting for connections to terminate) ~? - this message ~~ - send the escape character by typing it twice (Note that escapes are only recognized immediately after newline.)

Remove security limitations from PDF documents using ghostscript
Remove security from PDF document using this very simple command on Linux and OSX. You need ghostscript for this baby to work.

Intercept, monitor and manipulate a TCP connection.
This will handle multiple incoming connections. Also, found sed works best with -u flag (unbuffered io). Easiest way I've found to get ncat is to install nmap.

Loops over files, runs a command, dumps output to a file
In this case I'm selecting all php files in a dir, then echoing the filename and piping it to ~/temp/errors.txt. Then I'm running my alias for PHPCS (WordPress flags in my alias), then piping the PHPCS output to grep and looking for GET. Then I'm piping that output to the same file as above. This gets a list of files and under each file the GET security errors for that file. Extrapolate this to run any command on any list of files and pipe the output to a file. Remove the >> ~/temp/errors.txt to get output to the screen rather than to a file.


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