> The program runs perfectly on the two laptops, but not on my desktop. > > The command line for the file looks like: Decrypt.rb test1.in test2.in > <input.in That is indeed odd. You'd have to go down into the C to see why that is happening (and try to reproduce it with "straight C" or what not). Perhaps it is caused by a subtle difference in OS or msvcrt.dll version? Anyway, you could work around by noting that gets "by default" reads from the files passed as parameters: http://stackoverflow.com/questions/2294439/unexpected-gets-behavior-with-commandline-arguments-in-ruby-closed But I'd probably do something like $ ruby Decrypt.rb test1.in test2.in input.in file = File.open(ARGV.pop, 'r') file.gets GL. -rp -- Posted via http://www.ruby-forum.com/.