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OpenWrite

opens a file to write output to it, and returns an OutputStream object.

opens a new file in the default area for temporary files on your computer system.

MORE INFORMATION

OpenWrite deletes any existing contents in a file, and prepares to write output starting at the beginning of the file.

The following options can be given:

	BinaryFormat	False	whether to use binary format for the file
	CharacterEncoding	Automatic	what raw character encoding to use
	FormatType	InputForm	default format for printing expressions
	NumberMarks	$NumberMarks	when to use marks in approximate numbers
	PageWidth	78	number of character widths per line
	TotalWidth	Infinity	maximum number of character widths for a single expression

On computer systems that support pipes, OpenWrite runs the external program specified by command, and opens a pipe to send input to it.

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

OpenWrite resolves file names according to the procedure described in "Files and Streams".

OpenWrite returns OutputStream, 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.

SetOptions can be used to change the properties of an output stream, after it is already open.

Functions like Put and Write automatically open the files or pipes they need, if they are not already open.

With the default setting BinaryFormat->False, the setting for CharacterEncoding is taken to be .

OpenWrite always creates a new file that does not already exist, in the directory given by $TemporaryDirectory.

Basic Examples (1)

Create and open a new stream for writing:

Write an expression to the stream:

Close the stream:

Print the resulting file:

Create and open a new stream for writing:

Out[2]=

Write an expression to the stream:

Close the stream:

Out[4]=

Print the resulting file:

OpenAppend OpenRead Close Put Streams LinkCreate

Streams and Low-Level Input and Output

Basic Input & Output in Programs

File Operations

Files

Low-Level File Operations

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