Commands by ronnix (0)

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    bash: commands not found

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bash pause command
Waiting for a key stroke. You can use this with a ";" behind to build a command chain.

Get the 10 biggest files/folders for the current direcotry

Keep track of diff progress
When running a long `diff -r` over folders, this simulates a "verbose" mode where you can see where diff is in the tree. Replace $file with the first part of the path being compared.

Rotate all jpeg images in current folder, rename them to EXIF datetime and set files timestamp to EXIF datetime

List your interfaces and MAC addresses
Requires sysfs mounted on /sys - may only be useful for Linux systems. Could also use "printf '%-8s %s\n' $(basename $f) $(cat $f/address)" instead of echo.

Getting the last argument from the previous command

gag version of current date

Creating shortened URLs from the command line

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

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.

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