How to call shell commands from Ruby

Question

How do I call shell commands from inside of a Ruby program? How do I then get output from these commands back into Ruby?

Answer 1

We can achieve it in multiple ways.

Using Kernel#exec, nothing after this command is executed:

exec('ls ~')

Using backticks or %x

`ls ~`
=> "Applications\nDesktop\nDocuments"
%x(ls ~)
=> "Applications\nDesktop\nDocuments"

Using Kernel#system command, returns true if successful, false if unsuccessful and returns nil if command execution fails:

system('ls ~')
=> true