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Display which distro is installed
Works on Ubuntu

Find dead symbolic links
-L tells find to follow symbolic links, so -type l will only return links it can't follow (i.e., those that are broken).

Install Linux Kernel Headers on Debian-based systems
Install the Linux kernel headers for currently running kernel version on Debian-based systems via apt-get

Given process ID print its environment variables
Same as previous but compatible with BSD/IPSO

Run a command, store the output in a pastebin on the internet and place the URL on the xclipboard
The URL can then be pasted with a middle click. This is probably useful when trying to explain problems over instant messaging when you don't have some sort of shared desktop.

Follow tail by name (fix for rolling logs with tail -f)
If you use 'tail -f foo.txt' and it becomes temporarily moved/deleted (ie: log rolls over) then tail will not pick up on the new foo.txt and simply waits with no output. 'tail -F' allows you to follow the file by it's name, rather than a descriptor. If foo.txt disappears, tail will wait until the filename appears again and then continues tailing.

Check if network cable is plugged in and working correctly
with 'mii-tool -w eth0' you can watch the interface for changes of the link status

Perform a branching conditional
This will perform one of two blocks of code, depending on the condition of the first. Essentially is a bash terniary operator. To tell if a machine is up: $ ping -c1 machine { echo succes;} || { echo failed; } Because of the bash { } block operators, you can have multiple commands $ ping -c1 machine && { echo success;log-timestamp.sh }|| { echo failed; email-admin.sh; } Tips: Remember, the { } operators are treated by bash as a reserved word: as such, they need a space on either side. If you have a command that can fail at the end of the true block, consider ending said block with 'false' to prevent accidental execution

Solaris - check ports/sockets which process has opened

Capture video of a linux desktop


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