Open Scrn

Opens the screen directly for input and output as a file

Syntax
   Open Scrn [for mode] As [#]filenumber As Long

Usage
   Open Scrn [for mode] as [#]filenumber
      or
   result = Open Scrn( [for mode[,]] as [#]filenumber )

Parameters
   mode
      Either Input or Output.  If omitted, Output is assumed.
   filenumber
      An unused file number.

Return Value
   A 32 bit Long: a zero (0) is returned if Open Scrn() completed 
   successfully, otherwise a non-zero value is returned to indicate 
   failure.

Description
   This command opens the screen (in text or graphics screen mode) for both 
   input and output as a file, allowing to read/write from/to it with 
   normal file commands.

   This command may use direct access to the screen for speed in some 
   implementations, so  it should not be used when the input / output is 
   required to be redirected or piped with OS commands.    

   The normal screen commands, such as Color and Locate, do not work in 
   this mode, because they do not accept a file number.

   The [For Input|Output] clause is allowed for compatibility, but is 
   ignored.

   filenumber is an unused file number.

   An unused file number can be found using FreeFile.

   The error code returned by Open Scrn can be checked using Err in the 
   next line. The function version of  Open Scrn returns directly the error 
   code as a 32 bit Long.

Runtime errors:
   Open Scrn throws one of the following runtime errors:

   (1) Illegal function call
      * filenumber was not free at the time. use FreeFile to ensure that 
        filenumber is free.	

Example
   Dim a As String
   Open Scrn For Input  As #1
   Print #1,"Please write something and press ENTER"
   Line Input #1,a
   Print #1, "You wrote";a
   Close
   Sleep

Differences from QB
   * QB used OPEN "SCRN:" ...

See also
   * Open
   * Open Cons

