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opens a file to read data from, and returns an InputStream object.
  • OpenRead prepares to read from a file, starting at the beginning of the file.
  • On systems that support pipes, OpenRead["!command"] runs the external program specified by command, and opens a pipe to get input from it.
  • If OpenRead does not succeed in opening a particular file or pipe, it generates a message, and returns $Failed.
  • The function ReadList automatically opens files or pipes that it needs.
  • OpenRead returns InputStream["name", n], where name is the full name of a file or command, and n is a serial number that is unique across all streams opened in the current Mathematica session.
  • With the option BinaryFormat->True the stream is opened in binary format, so that no textual interpretation of newlines or other data is done.
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