ns_OpenFile

 ns_OpenFile   Opens a neural data file

    Usage:
        [ns_RESULT, hFile] = ns_OpenFile('filename.ext')

    Description:
        Opens the file specified by filename and returns a file handle, 
        hFile, that is used to access the opened file.

    Parameters:
        filename    Pointer to a null-terminated string that specifies the
                    name of the file to open. 

    Return Values:
        hFile       Handle/Indentification number to the opened file.
        ns_RESULT   This function returns ns_OK if the file is successfully
                    opened. Otherwise one of the following error codes is 
                    generated:

                        ns_TYPEERROR    Library unable to open file type
                        ns_FILEERROR    File access or read error 

    Remarks:
        All files are opened for read-only, as no writing capabilities have
        been implemented.  If the command succeeds in opening the file, the
        application should call ns_CloseFile for each open file before 
        terminating.

        This function has to be called before any other Neuroshare function
        is called. 

    Copyright (C) 2003 Neuroshare Project
    Author: Almut Branner
    Last modification: 6/20/2003