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timuruski/test.rb

Created July 24, 2013 16:55
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Trying to tease out STDIN/OUT interactivity for Ruby scripts
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test.rb
puts "STDIN: #{STDIN.tty?}, $stdin: #{$stdin.tty?}"
puts "STDOUT: #{STDOUT.tty?}, $stdout: #{$stdout.tty?}"
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test.sh
#!/usr/bin/env bash
ruby test.rb
@timuruski
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Try running the Ruby script directly, the shell script and running it through a bash invocation and sub-shell, the value of tty? is always true.

@timuruski
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$ ruby test.rb
> STDIN: true, $stdin: true
> STDOUT: true, $stdout: true

$ ruby test.rb | cat
> STDIN: true, $stdin: true
> STDOUT: false, $stdout: false

$ echo | ruby test.rb | cat
STDIN: false, $stdin: false
STDOUT: false, $stdout: false

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