Commands by cbrchrt (1)

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Check if a domain is available and get the answer in just one line
Returns nothing if the domain exists and 'No match for domain.com' otherwise.

View non-printing characters with cat
Useful to detect number of tabs in an empty line, DOS newline (carriage return + newline). A tool that can help you understand why your parsing is not working.

Show network throughput
Real gurus don't need fancy tools like iftop or jnettop.

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Do a search-and-replace in a file after making a backup

rsync + find
rsync from source to dest all between >30

Show UDID of iPhone
Display the serial of the iPhone (aka UDID).

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.

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Kill all processes that don't belong to root/force logoff
explanation: grep -- displays process ids -v -- negates the matching, displays all but what is specified in the other options -u -- specifies the user to display, or in this case negate The process loops through all PIDs that are found by pgrep, then orders a forced kill to the processes in numerical order, effectively killing the parent processes first including the shells in use which will force the users to logout. Tested on Slackware Linux 12.2 and Slackware-current

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