Commands by servermanaged (56)

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A child process which survives the parent's death (for sure)
Test scenario: * Open xterm (or konsole, ...) * Start xeyes with: ( xeyes & ) * Close the xterminal The xeyes process should be still running.

Validate openssh key & print checksum

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

run a command whenever a file is touched
This is useful if you'd like to see the output of a script while you edit it. Each time you save the file the command is executed. I thought for sure something like this already exists - and it probably does. I'm on an older system and tend to be missing some useful things. Examples: $ ontouchdo yourscript 'clear; yourscript somefiletoparse' Edit yourscript in a separate window and see new results each time you save. $ ontouchdo crufty.html 'clear; xmllint --noout crufty.html 2>&1 | head' Keep editing krufty.html until the xmllint window is empty. Note: Mac/bsd users should use stat -f%m. If you don't have stat, you can use perl -e '$f=shift; @s=stat($f); print "$s[9]\n";' $1

Wait for an already launched program to stop before starting a new command.
Referring to the original post, if you are using $! then that means the process is a child of the current shell, so you can just use `wait $!`. If you are trying to wait for a process created outside of the current shell, then the loop on `kill -0 $PID` is good; although, you can't get the exit status of the process.

check open ports without netstat or lsof

scheduled jobs

Weather on the Command line
Get your weather from a weather station just blocks from your home. Go to http://www.wunderground.com/wundermap/ and find a weather station near you. Click on a temperature bubble for that area. When the window pops up, click on hypertext link with the station ID, then on the bottom right of the page, click on the Current Conditions XML. Thats your link! Good luck!

determine if tcp port is open
Requires netcat.

List programs with open ports and connections
I prefer to use this and not the -n variety, so I get DNS-resolved hostnames. Nice when I'm trying to figure out who's got that port open.


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