Looping is great for working over sequences of data in an iterative fashion, but sometimes, when you're doing all that work, you get lots of irrelevant output. Enter our little magician: the output redirection operator, >. This operator directs output to a specified file or file descriptor. We've talked about file descriptors, they are integers that the OS uses to identify a file handle that has been opened, and by default there are three opened for every process: stdin, stdout, and stderr. The default file descriptors, denoted by fd#, are fd0 for standard input, fd1 for standard output, and fd2 for standard error. The > operator by default, redirects stdout, the equivalent of 1>, unless it's preceded by an integer file-descriptor. Let's see some examples of output redirection, before we get lost...
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