Commands by donjuanica (2)

What's this? is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

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Enable verbose boot in Mac OS X Open Firmware

print all network interfaces' names and IPv4 addresses
ifconfig can't properly display interface's name longer 9 symbols,also it can't show IPs added thru ip command, so 'ip' should be used instead. This alias properly shows long names, bond interfaces and all interface aliases. loopback interface is ignored, since its IP is obvious

list block devices
Shows all block devices in a tree with descruptions of what they are.

Go to the previous sibling directory in alphabetical order
Based on linkinpark342 suggestion. Sometimes you have to browse your way through a lot of sub-directories. This command cd to the previous sub-directory in alphabetical order. For example, if you have the directories "lectures/01-intro", "lectures/02-basic", "lectures/03-advanced" and so on, and your PWD is "02-basic", it jumps to "01-intro".

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)

Processes by CPU usage

Reverse ssh
Both hosts must be running ssh and also the outside host must have a port forwarded to port 22.

Encode a string using ROT47
This command will encode a string using the ROT47 cipher.

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; }|| { echo failed;; } 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

Insert the last command without the last argument (bash)
$/usr/sbin/ab2 -f TLS1 -S -n 1000 -c 100 -t 2 then $!:- is the same as $/usr/sbin/ab2 -f TLS1 -S -n 1000 -c 100 -t 2

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