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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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Renaming a file without overwiting an existing file name
Sometimes in a hurry you may move or copy a file using an already existent file name. If you aliased the cp and mv command with the -i option you are prompted for a confirmation before overwriting but if your aliases aren't there you will loose the target file! The -b option will force the mv command to check if the destination file already exists and if it is already there a backup copy with an ending ~ is created.

Start screen in detached mode
Start screen in detached mode, i.e., already running on background. The command is optional, but what is the purpose on start a blank screen process that way? It's useful when invoking from a script (I manage to run many wget downloads in parallel, for example).

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Auto Get Missing Launchpad Keys
You can choose these mirror servers to get gpg keys, if the official one ever goes offline #(replace with your country code fr, en, de,etc)

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.

Changing the terminal title to the last shell command
You can set the previous bash command as the terminal title by this command. Explanation: -trap assigns a command to execute at a given bash signal. -in the $BASH_COMMAND you find the last command -you can set the terminal title with the escape sequence: \e]0;this is the title\007 -to let the echo care about the backslashes give the -e to it Since trap is a built in bash command you find more informatin in 'man bash'for more Source:

keep a log of the active windows
This logs the titles of the active windows, thus you can monitor what you have done during which times. (it is not hard to also log the executable name, but then it is gets too long)

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"

Dump HTTP header using wget
Let me suggest using wget for obtaining the HTTP header only as the last resort because it generates considerable textual overhead. The first ellipsis of the sample output stands for Spider mode enabled. Check if remote file exists. --2009-03-31 20:42:46-- Resolving Connecting to||:80... connected. HTTP request sent, awaiting response... and the second one looks for Length: 438 [text/html] Remote file exists and could contain further links, but recursion is disabled -- not retrieving.

easily strace all your apache processes
This version also attaches to new processes forked by the parent apache process. That way you can trace all current and *future* apache processes.

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