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

  • OpenAppend[" file "] opens a file to append output to it, and returns an OutputStream object.
  • The following options can be given:
  • 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 OpenRead 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 Section A.6.1.
  • 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.
  • Setting the option DOSTextFormat->True causes newlines specified by \n to be output as \n\r pairs, suitable for text-mode files on MS-DOS and related systems.
  • See the Mathematica book: Section 2.11.3.
  • See also: Close, Put, Streams, LinkCreate.