Commands by srand (1)

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Protect directory from an overzealous rm -rf *
Forces the -i flag on the rm command when using a wildcard delete.

Copy via tar pipe while preserving file permissions (run this command as root!)
It's the same like 'cp -p' if available. It's faster over networks than scp. If you have to copy gigs of data you could also use netcat and the tar -z option in conjunction -- on the receiving end do: # nc -l 7000 | tar -xzvpf - ...and on the sending end do: # tar -czf - * | nc otherhost 7000

Limit the transfer rate and size of data over a pipe
This example will close the pipe after transferring 100MB at a speed of 3MB per second.

Define an alias with a correct completion
In Bash, when defining an alias, one usually loses the completion related to the function used in that alias (that completion is usually defined in /etc/bash_completion using the complete builtin). It's easy to reuse the work done for that completion in order to have smart completion for our alias. That's what is done by this command line (that's only an example but it may be very easy to reuse). Note 1 : You can use given command line in a loop "for old in apt-get apt-cache" if you want to define aliases like that for many commands. Note 2 : You can put the output of the command directly in your .bashrc file (after the ". /etc/bash_completion") to always have the alias and its completion

Check if you work on a virtual/physical machine in Linux
Command used to know if we are working on a virtual or physical machine. This command will use the dmidecode utility to retrieve hardware information of your computer via the BIOS. Run this command as root or with sudo.

Arch Linux: Always install software without asking
Adding this alias to ~/.bashrc or, better yet, the system-wide /etc/bash.bashrc (as in my setup) will make it possible to not only run pacman as any user without needing to prepend sudo but will also ensure that it always assumes that the user knows what he or she is doing. Not the best thing for large multi-user enterprise setups at all to say the least, but for home (desktop) use, this is a fantastic time-saver.

Restore deleted file from GIT repository
This command will automatically find the latest version of the file that was deleted and restore it to it's previous location. If, of course, your file was kept in a git repository... I found this command on http://stackoverflow.com/a/1113140

rsync over ssh via non-default ssh port
tested on cygwin and Fedora 9 . good to remember for those jobs where you cannot set a site-specific connect option in your ~/.ssh/config file.

Find the package that installed a command

dump a single table of a database to file


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