get system free memory in ruby

To get the amount of free system memory in Ruby, you can execute shell commands using the system method and the free -m command. Here's an example code snippet:

main.rb
memory = `free -m`
free_memory = memory.split("\n")[1].split(" ")[3].to_i
puts "Free memory: #{free_memory} MB"
112 chars
4 lines

In this code, we execute the free -m command and capture its output using backticks. We then split the output by lines, select the second line, split it by spaces, and select the fourth element (which represents the amount of free memory in MB). Finally, we convert this value to an integer and print it to the console.