Commands by YouM (2)

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get all Google ipv4/6 subnets for a iptables firewall for example (updated version)
google has added 2 more netblocks...

converting vertical line to horizontal line

display a one-liner of current nagios exit statuses. great with netcat/irccat

Generate a random password 30 characters long

Shell function to create a directory named with the current date, in the format YYYYMMDD.
Creates a directory named with the current date, in the format YYYYMMDD. If you give it a directory name as an argument, it will create the new directory inside the specified directory. This is an alternative to command #1993.

List all symbolic links in a directory matching a string
Finds all symbolic links in the specified directory which match the specified string pattern. I used this when upgrading from an Apple-supported version of Java 6 (1.6.0_65) to an Oracle-supported version (1.7.0_55) on Mac OS X 10.8.5 to find out which executables were pointing to /System/Library/Frameworks/JavaVM.framework/Versions/Current/Commands (Apple version) vs. /Library/Java/JavaVirtualMachines/jdk1.7.0_55.jdk/Contents/Home/bin (Oracle version). However, it appears the current JDK installation script already takes care of modifying the links.

Remove today's installed packages

Compare two directory trees.
This uses Bash's "process substitution" feature to compare (using diff) the output of two different process pipelines.

Reuse all parameter of the previous command line
!* is all of the arguments to the previous command rather than just the last one. This is useful in many situations. Here's a simple example: $ vi cd /stuff oops! [exit vi, twice] $ !* expands to: cd /stuff

Print the IPv4 address of a given interface


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