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Built-in Mathematica Symbol

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OpenAppend

OpenAppend["file"]
opens a file to append output to it, and returns an OutputStream object.

MORE INFORMATION

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, OpenAppend["!command"] runs the external program specified by command, and opens a pipe to send input to it.

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

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

OpenAppend returns OutputStream["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.

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 "ASCII".

Basic Examples (1)

Create a file and write an expression to it:

Read the file:

Open the file using OpenAppend:

Write an expression and close the stream:

OpenWrite OpenRead Close PutAppend Streams LinkCreate

Streams and Low-Level Input and Output

Low-Level File Operations

New in 1 | Last modified in 5.1

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