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Select and Edit a File in the Current Directory
This command displays a simple menu of file names in the current directory. After the user made a choice, the command invokes the default editor to edit that file. * Without the break statement, the select command will loop forever * Setting the PS3 prompt is optional * If the user types an invalid choice (such as the letter q), then the variable $f will become an empty string. * For more information, look up the bash's select command

a simple bash one-liner to create php file and call php function

Check ps output to see if file is running, if not start it
This comes in handy if you have daemons/programs that have potential issues and stop/disappear, etc., can be run in cron to ensure that a program remains up no matter what. Be advised though, if a program did core out, you'd likely want to know why (gdb) so use with caution on production machines.

check open ports without netstat or lsof

Cap apt-get download speed
apt-get is pretty aggressive when it downloads, potentially hogging the bandwidth of your network. The 25 is in KB, change this to your needs.

Convert CSV to JSON - Python3 and Bash function
Based / Inspired by malathion's below command http://www.commandlinefu.com/commands/view/20528/convert-csv-to-json Is written for python3 and is very easy to use csv2json *csv will convert all files ending in csv to json eg csv2json file.csv will output a file to file.json Validity of json tested in python3 and below site https://jsonformatter.curiousconcept.com/

Find files with size over 100MB and output with better lay-out

Kill all processes that listen to ports begin with 50 (50, 50x, 50xxx,...)
Run netstat as root (via sudo) to get the ID of the process listening on the desired socket. Use awk to 1) match the entry that is the listening socket, 2) matching the exact port (bounded by leading colon and end of column), 3) remove the trailing slash and process name from the last column, and finally 4) use the system(…) command to call kill to terminate the process. Two direct commands, netstat & awk, and one forked call to kill. This does kill the specific port instead of any port that starts with 50. I consider this to be safer.

display emerge.log date in a human friendly way
gentoo only or gentoo-like linux distributions.

Show an application's environment variables


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