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monitor the last command run

extract element of xml
poor man's xml parser :)

Generate a Change Log with git
Generate a changelog between the v1 and v2 tags

Pick a random line from a file

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

View dmesg output in human readable format

Perform a branching conditional
This will perform one of two blocks of code, depending on the condition of the first. Essentially is a bash terniary operator. To tell if a machine is up: $ ping -c1 machine { echo succes;} || { echo failed; } Because of the bash { } block operators, you can have multiple commands $ ping -c1 machine && { echo success;log-timestamp.sh }|| { echo failed; email-admin.sh; } Tips: Remember, the { } operators are treated by bash as a reserved word: as such, they need a space on either side. If you have a command that can fail at the end of the true block, consider ending said block with 'false' to prevent accidental execution

prevent large files from being cached in memory (backups!)
We all know... $ nice -n19 for low CPU priority.   $ ionice -c3 for low I/O priority.   nocache can be useful in related scenarios, when we operate on very large files just a single time, e.g. a backup job. It advises the kernel that no caching is required for the involved files, so our current file cache is not erased, potentially decreasing performance on other, more typical file I/O, e.g. on a desktop.   http://askubuntu.com/questions/122857 https://github.com/Feh/nocache http://packages.debian.org/search?keywords=nocache http://packages.ubuntu.com/search?keywords=nocache   To undo caching of a single file in hindsight, you can do $ cachedel   To check the cache status of a file, do $ cachestats

Create MySQL-Dump, copy db to other Server and upload the db.
This option makes a copy of your current db and via ssh it transfer to the server you specify and upload the database to the specific User & Password you specify (Note the db User & Pass, can be different from the one you use in the other server) If you are going to use "localhost" as your main db remove (-h) and youst add "localhost"

"hidden" remote shell
opens a "hidden" remote shell (login will not appear in "last" for example). This is not really hidden, because the login will be shown in auth.log and the process is visible anyways. ssh -T = Disable pseudo-tty allocation. bash -i = interactive shell


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