Commands by scurge (1)

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View all new log messages in real time with color
This will show all changes in all log files under /var/log/ that are regular files and don't end with `gz` nor with a number

Prints any IP out of a file

Prepend a text to a file.
Syntax: $ prepend content to add [filename] Uses ed, so no temp files created.

Determine what version of bind is running on a dns server.
Due to the recent dynamic update vulnerability with bind, I was forced to dig a little deeper into dig...

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"

Convert the contents of a directory listing into a colon-separated environment variable
Useful for making a CLASSPATH out of a list of JAR files, for example. Also: export CLASSPATH=.:$(find ./lib -name '*.jar' -printf '%p:')

find and reduce 8x parallel the size of JPG images without loosing quality via jpegoptim

Compare two directories
Output of this command is the difference of recursive file lists in two directories (very quick!). To view differences in content of files too, use the command submitted by mariusbutuc (very slow!): $ diff -rq path_to_dir1 path_to_dir2

Find the package that installed a command

Get ethX mac addresses
I much prefer using /sbin/ip over /sbin/ifconfig for most everything. I find the interface and output to be much more consistent and it has many abilities that ifconfig, route, etc. do not. To get the mac address for only one interface, add 'show dev [interface]' to the 'ip link' part of the command: ip link show dev eth0 | grep 'link/ether' | awk '{print $2}' . Also, both this command and the ifconfig one do not require root access to run, so the sudo is not necessary.


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