Open Err

Opens both the standard input (stdin) and standard error (stderr) streams, 
using it as if it were file operations.

Syntax
	KeyPgOpenOpen Err [for mode] KeyPgAsAs [#]filenumber KeyPgAsAs KeyPgLongLong

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

Parameters
	mode
		Ignored.
	filenumber
		An unused file number.

Return Value
	A 32 bit KeyPgLongLong: a zero is returned if Open Err() completed successfully, 
	otherwise a non-zero value is returned to indicate failure.

Description
	This command opens stdin to read from and stderr to write to the console 
	allowing read and write operations with normal file commands.

	stderr is an output stream different from stdout allowing error messages 
	to be redirected separately from the main console output.

	The normal console commands, such as KeyPgColorColor and KeyPgLocateLocate, do not work in 
	this mode, because they do not accept a file number.
	The KeyPgTabTab keyword, regardless of the given column number, is always 
	interpreted as a simple comma (,) (next output will take place at the 
	next 14 column boundary).

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

	The error code returned by Open Err can be checked using KeyPgErrErr in the next 
	line. The function version of  Open Err returns directly the error code 
	as a 32 bit KeyPgLongLong.

Runtime errors:
	Open Err throws one of the following ProPgErrorHandlingruntime errors:

	(1) Illegal function call
		* Filenumber was not free at the time. use KeyPgFreefileFreeFile to ensure that 
		  filenumber is free.

Example
	Dim a As String
	Open Err 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
	* New to FreeBASIC

See also
	* KeyPgOpenOpen

