Well, learned something today after reading a bit further in the thread: ruby -e 'x = "a\n25\n" ; if x =~ /^\d+$/ ; puts "yes" ; else ; puts "no" ; end'

Well, learned something today after reading a bit further in the thread: ruby -e 'x = "a\n25\n" ; if x =~ /^\d+$/ ; puts "yes" ; else ; puts "no" ; end' yes Good to know.