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Documentation / Mathematica / Built-in Functions / Input and Output / File Input /

OpenRead

FilledSmallSquare OpenRead["file"] opens a file to read data from, and returns an InputStream object.

FilledSmallSquare OpenRead prepares to read from a file, starting at the beginning of the file.

FilledSmallSquare On systems that support pipes, OpenRead["!command"] runs the external program specified by command, and opens a pipe to get input from it.

FilledSmallSquare If OpenRead does not succeed in opening a particular file or pipe, it generates a message, and returns $Failed.

FilledSmallSquare OpenRead resolves file names according to the procedure described in Section A.6.1.

FilledSmallSquare The function ReadList automatically opens files or pipes that it needs.

FilledSmallSquare 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.

FilledSmallSquare Setting the option DOSTextFormat->True causes all input to be treated as coming from a text-mode file on an MS-DOS or related system. This means that \r\n pairs are interpreted as single newlines, and ControlKeyLeftModifiedZRightModified is interpreted as EndOfFile.

FilledSmallSquare See Section 2.12.8.

FilledSmallSquare See also: Close, Read, ReadList, Streams, LinkCreate.

FilledSmallSquare New in Version 1; modified in 3.