Commands using cut (586)

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Extract the contents of an RPM package to your current directory without installing them.
This assumes you have the 'rpm', 'rpm2cpio' and 'cpio' packages installed. This will extract the contents of the RPM package to your current directory. This is useful for working with the files that the package provides without installing the package on your system. Might be useful to create a temporary directory to hold the packages before running the extraction: $ mkdir /tmp/new-package/; cd /tmp/new-package

Export MySQL tables that begin with a string

ping a host until it responds, then play a sound, then exit
Audio acknowledgement for host availability. When running the command from a Linux systems, you can use "festival" or "espeak" instead of "say".

Find and copy files from subdirectories to the current directory

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.

Gets the english pronunciation of a phrase
Usage examples: say hello say "hello world" say hello+world

Click on a GUI window and show its process ID and command used to run the process
This command is useful when you want to know what process is responsible for a certain GUI application and what command you need to issue to launch it in terminal.

check open ports without netstat or lsof

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"

Use Kernighan & Ritchie coding style in C program


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