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Update all ant packages installed in gentoo
Update all "ant" packages installed on Gentoo

Shows a specific process memory usage

Use Perl like grep
If you've ever tried "grep -P" you know how terrible it is. Even the man page describes it as "highly experimental". This function will let you 'grep' pipes and files using Perl syntax for regular expressions. The first argument is the pattern, e.g. '/foo/'. The second argument is a filename (optional).

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Get duration of an audio file in seconds.
This is an alternative to #9131. ffmpeg didn't work on my .au files, though it did on the .wav ones. Also useful if you don't have ffmpeg but do have sox. Handily, sox already reports in seconds (decimal).

Crash bash, in case you ever want to for whatever reason
This is a very hackish way to do it that I'm mainly just posting for fun, and I guess technically can more accurately be said to result in undefined behavior. What the command does is tell the shell to treat libpng like it's a shell plugin (which it's most certainly not) and attempt to install a "png_create_read" command from the library. It looks for the struct with the information about the command; since it's always the command name followed by "_struct", it'll look for a symbol called "png_create_read_struct". And it finds it, since this is the name of one of libpng's functions. But bash has no way to tell it's a function instead of a struct, so it goes ahead and parses the function's code as if it was command metadata. Inevitably, bash will attempt to dereference an invalid pointer or whatever, resulting in a segfault.

keep an eye on system load changes
helps you keep watch on the load of a system, without having to stare constantly at the terminal. The -d argument to watch highlights the difference from the last run, making it easier to note how the load is fluctuating. The sed command just strips off the information about how long the box has been up, and how many users are logged in.

check open ports without netstat or lsof

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Formatted list - WWNs of all LUNs
Use `scsi_id` to positively identify which LUNs are which (i.e. compare with the list of LUNs you created on your disk array) (shown: RHEL5 usage) Debian usage: $ # for i in /dev/sd* ; do wwn=`/lib/udev/scsi_id -g --device $i` ; [ "$wwn" != "" ] && echo -e ${i##*/}'\t'$wwn ;done


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