Commands by varghjarta (2)

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Restart Xen XAPI
Restarts the XAPI service on the host, mostly used by Xen Center. It does not affect any running VMs, just the Xen client tools that may be connected. On my list as XAPI frustratingly keeps running out of memory and getting killed off.

Create a new file

Random unsigned integer
Reads 4 bytes from the random device and formats them as unsigned integer between 0 and 2^32-1.

show the date every rpm was installed
the newest rpms are at the top; individual packages can also be queried this way: rpm --last -q package

Colorize make, gcc, and diff output
Colorize output of make, gcc/g++ or diff, making it easier to read at a glance. They are not distributed with make, diff or gcc, but are usually available in the repositories.

Random numbers with Ruby
There's been a few times I've needed to create random numbers. Although I've done so in PERL, I've found Ruby is actually faster. This script generates 20 random "10" digit number NOT A RANDOM NUMBER. Replace 20 (1..20) with the amount of random numbers you need generated

Remove spaces from filenames - through a whole directory tree.
An example of zsh glob qualifiers.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

A DESTRUCTIVE command to render a drive unbootable
Overwrites the boot sector. Since this doesn't overwrite any data, you can usually recover by re-creating the partition table exactly the same as before you zeroed it. This can also help sometimes if you install a new drive in a Windows machine which can't read it.

command line fu roulette
retrieves the html from a random command line fu page, then finds commands on the page and prints them alternatively, pipe to bash (add "| bash" to the end) to execute the command (very risky) edit: had to adjust to properly display the portion that replaces HTML characters (e.g. " -> ")


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