Commands by dratini0 (1)

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Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Get the full path to a file
Useful in scripts when the file is passed in as an argument. Eg. $ filepath=$(realpath $1)

cp the file
Copy the file with the given .extension at the source file's location. Eliminates the typing of long paths again and again.

Show current working directory of a process

Fetch the current human population of Earth

Efficiently extract lines between markers
GNU Sed can 'address' between two regex, but it continues parsing through to the end of the file. This slight alteration causes it to terminate reading the input file once the STOP match is made. In my example I have included an extra '/START/d' as my 'start' marker line contains the 'stop' string (I'm extracting data between 'resets' and using the time stamp as the 'start'). My previous coding using grep is slightly faster near the end of the file, but overall (extracting all the reset cycles in turn) the new SED method is quicker and a lot neater.

Check if a remote port is up using dnstools.com (i.e. from behind a firewall/proxy)
Shell function; returns 0 if the port is up, 1 otherwise (check $? after executing). First parameter: IP address/hostname Second parameter: port number There is no error checking for the input parameters.

List the CPU model name
Information for only one core.

Lists all listening ports together with the PID of the associated process
The PID will only be printed if you're holding a root equivalent ID.

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"


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