Commands by mtaqwim (1)

What's this? is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

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Show GCC-generated optimization commands when using the "-march=native" or "-mtune=native" switches for compilation.
You can tell GCC to automatically select optimization commands and produce optimized code for the local machine (the one compiling the code), but you can't normally see what switches have been selected and used unless you append a "-v" and pause compilation.

Get the current gold price
Returns the current price of a troy ounce of gold, in USD. Requires the "jq" JSON parser.

Show all mergeinfo for a svn subtree

convert uppercase files to lowercase files

UPS Tracking Script

hanukkah colored bash prompt
blue and yellow colored bash prompt for a Hanukkah celebration on your box

Copy an element from the previous command
You can specify a range via '-'.

Safe Russian Roulette (only echo, don't delete files)
Shows "Bang!" in a chance of 1 out of 6, like in the original game with the gun (spin every round). Otherwise, echoes "Click...". If feeling brave you can also do: $[ $[ $RANDOM % 6 ] == 0 ] && echo 'Bang!' && a really killer command || echo 'Click...'

Synchronize date and time with a server over ssh
Shorter, easier to remember version of cmd#7636 NTP is better, but there are situations where it can't be used. In those cases, you can do this to sync the local time to a server.

Upgrading packages. Pacman can update all packages on the system with just one command. This could take quite a while depending on how up-to-date the system is. This command can synchronize the repository databases and update the system's packages.
Warning: Instead of immediately updating as soon as updates are available, users must recognize that due to the nature of Arch's rolling release approach, an update may have unforeseen consequences. This means that it is not wise to update if, for example, one is about to deliver an important presentation. Rather, update during free time and be prepared to deal with any problems that may arise. Pacman is a powerful package management tool, but it does not attempt to handle all corner cases. Read The Arch Way if this causes confusion. Users must be vigilant and take responsibility for maintaining their own system. When performing a system update, it is essential that users read all information output by pacman and use common sense. If a user-modified configuration file needs to be upgraded for a new version of a package, a .pacnew file will be created to avoid overwriting settings modified by the user. Pacman will prompt the user to merge them. These files require manual intervention from the user and it is good practice to handle them right after every package upgrade or removal. See Pacnew and Pacsave Files for more info. Tip: Remember that pacman's output is logged in /var/log/pacman.log.

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