Commands by keymon (18)

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Get the SAN (subjectAltName) of a site's certificate.
Based on http://stackoverflow.com/questions/13127352/checking-alternative-names-for-a-san-ssl-cert Replace "facebook.com" with the desired hostname.

Lookup errno defintions
Calls the POSIX strerror() function to look up the meaning of integer ERRNOs set by some functions.

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

Rename .JPG to .jpg recursively
Recursively rename .JPG to .jpg using standard find and mv. It's generally better to use a standard tool if doing so is not much more difficult.

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

List the Sizes of Folders and Directories
I wanted an easy way to list out the sizes of directories and all of the contents of those directories recursively.

List programs with open ports and connections
I prefer to use this and not the -n variety, so I get DNS-resolved hostnames. Nice when I'm trying to figure out who's got that port open.

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"

Matrix Style

check open ports without netstat or lsof


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