Can't find "rackup" command?

http://titusd.co.uk/2010/04/07/a-beginners-sinatra-tutorial

I was trying to run rackup config.ru from the command line as instructed in the tutorial above in section 4. It ended up saying "No command 'rackup' found".

Any idea what happened?

Solution

Using rackup1.8 config.ru instead of rackup config.ru solved my problem. But I am not terribly sure what happened, though.

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