Commands by Karakh (2)

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change directory to actual path instead of symlink path
If you use symlinks a lot, especially nested symlinks, this puts you back on the absolute path to command-line-fu-nirvana. (Note the backticks around pwd).

Display Spinner while waiting for some process to finish
alternatively, run the spinner for 5 seconds: timeout 5 bash -c 'spinner=( Ooooo oOooo ooOoo oooOo ooooO oooOo ooOoo oOooo); while true; do for i in ${spinner[@]}; do for j in seq 0 ${#i}; do echo -en "\b\b"; done; echo -ne "${i}"; sleep 0.2; done; done'

How many days until the end of the year

mtr, better than traceroute and ping combined
mtr combines the functionality of the traceroute and ping programs in a single network diagnostic tool. As mtr starts, it investigates the network connection between the host mtr runs on and HOSTNAME. by sending packets with purposly low TTLs. It continues to send packets with low TTL, noting the response time of the intervening routers. This allows mtr to print the response percentage and response times of the internet route to HOSTNAME. A sudden increase in packetloss or response time is often an indication of a bad (or simply over‐loaded) link.

diff the same file in two directories.
This is useful when you're diffing two files of the same name in radically different directory trees. For example: Set $ path1='/some/long/convoluted/path/to/all/of/your/source/from/a/long/dead/machine' then $ path2='/local/version/of/same/file' then run the command. Much easier on the eyes when you're looking back across your command history, especially if you're doing the same diff over and over again.

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"

output your microphone to a remote computer's speaker

Remove duplicate lines whilst keeping empty lines and order
Remove duplicate lines whilst keeping order and empty lines

OpenDns IP update via curl
Your IP is resolved by OpenDns Server (like a caller ID telephone, every server knows who is calling ;-) Change user:password by yours Be Happy

Get playlist for Livestream on YouTube


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