Commands by detert (2)

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Create a mirror of a local folder, on a remote server
Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)

Target a specific column for pattern substitution
Awk replaces every instance of foo with bar in the 5th column only.

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"

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"

Make directories for and mount all iso files in a folder

Terrorist threat level text

Get your external IP address if your machine has a DNS entry
Using DynDNS or a similar service not only allows access to your home machine from outside without needing to know what IP the ISP has assigned to it but it also comes in handy if you want to know your external IP address. The only purpose of the sed command is to remove the leading "host.na.me has address " part from the output. If you don't need to discard it you can simply use $ host $HOSTNAME

Watch the progress of 'dd'
Running this code will execute dd in the background, and you'll grab the process ID with '$!' and assign it to the 'pid' variable. Now, you can watch the progress with the following: $ while true; do kill -USR1 $pid && sleep 1 && clear; done The important thing to grasp here isn't the filename or location of your input or output, or even the block size for that matter, but the fact that you can keep an eye on 'dd' as it's running to see where you are at during its execution.

Get windows IPv4 and nothing else
May be useful to get user's ip address over the phone, as users struggle to read through a long ipconfig result.

apt-get via sudo
An apt-get wrapper function which will run the command via sudo, but will run it normally if you're only downloading source files. This was a bit of an excuse to show off the framework of $ cmd && echo true || echo false ...but as you can see, you must be careful about what is in the "true" block to make sure it executes without error, otherwise the "false" block will be executed. To allow the apt-get return code to pass through, you need to use a more normal if/else block: $ apt-get () { if [ "$1" = source ]; then command apt-get "$@"; else sudo apt-get "$@"; fi }


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