Commands by Cont3mpo (2)

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Print a random 8 digit number
Don't need to pipe the output into rs if you just tell jot to use a null separator character.

a function to create a box of '=' characters around a given string.
First argument: string to put a box around. Second argument: character to use for box (default is '=') Same as command #4948, but shorter, and without the utility function.

Look for English words in /dev/urandom
* to get the English dictionary: wget http://www.mavi1.org/web_security/wordlists/webster-dictionary.txt

Find commets in jpg files.
Finds comments in jpg files, but I can't figure out how to exclude (in output) files without comments.

Retry the previous command until it exits successfully
Executes the previously-run command constantly until it returns 0 (success). Put a

Get full from half remembered commands
Show all commands having the part known by you. Eg: $apropos pdf | less

Rename all .jpeg and .JPG files to .jpg

Read and write to TCP or UDP sockets with common bash tools
Ever needed to test firewalls but didn't have netcat, telnet or even FTP? Enter /dev/tcp, your new best friend. /dev/tcp/(hostname)/(port) is a bash builtin that bash can use to open connections to TCP and UDP ports. This one-liner opens a connection on a port to a server and lets you read and write to it from the terminal. How it works: First, exec sets up a redirect for /dev/tcp/$server/$port to file descriptor 5. Then, as per some excellent feedback from @flatcap, we launch a redirect from file descriptor 5 to STDOUT and send that to the background (which is what causes the PID to be printed when the commands are run), and then redirect STDIN to file descriptor 5 with the second cat. Finally, when the second cat dies (the connection is closed), we clean up the file descriptor with 'exec 5>&-'. It can be used to test FTP, HTTP, NTP, or can connect to netcat listening on a port (makes for a simple chat client!) Replace /tcp/ with /udp/ to use UDP instead.

Edit a file inside a compressed archive without extracting it
If you vim a compressed file it will list all archive content, then you can pickup any of them for editing and saving. There you have the modified archive without any extra step. It supports many file types such as tar.gz, tgz, zip, etc.

List available upgrades from apt (package names only)
Usefull if you only want to see the package names, or if you want to use them in a script.


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