Commands by John_W (10)

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Backup all MySQL Databases to individual files
Backs up all databases, excluding test, mysql, performance_schema, information_schema. Requires parallel to work, install parallel on Ubuntu by running: sudo aptitude install parallel

listen to ram

Super Speedy Hexadecimal or Octal Calculations and Conversions to Decimal.
^Hexadecimal Ten minus Octal Ten is Eight(in Decimal). $ echo "$(( 0xaf )) = $(( 0257 ))" ^Hexadecimal AF and Octal 257 are both Decimal 175.

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"

Extract the emoticons regex from a running skype process
Skype has an internal regex which depicts the emoticons it supports. However you cannot simply search the binary file for it. This small 181 character line will do just that, provided skype is running. And of course, only works in linux.

check open ports without netstat or lsof

find the path of the java called from the command line
The output will likely point to '/etc/alternatives/java'. So find out where that points by issuing ls -l like this: ls -l /etc/alternatives/java

Simple top directory usage with du flips for either Linux or base Solaris
No need to type out the full OR clause if you know which OS you're on, but this is easy cut-n-paste or alias to get top ten directories by singleton. To avoid the error output from du -xSk you could always 2>/dev/null but you might miss relevant STDERR.

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

Generate random valid mac addresses
Ruby version. Also, a perl version: $perl -e 'printf("%.2x.",rand(255))for(1..5);printf("%.2x\n",rand(255))'


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