• an integer:
  • the identifier of the external file. This identifier will be used by all the functions for handling the external files.
  • -1 if an error occurred. To get more details on the error, use ErrorInfo with the errMessage constant.
• New in version 28
  a variable of type DiskFile. If an error occurs, the ErrorOccurred variable is set to True. To get more details on the error, use ErrorInfo with the errMessage constant.
  Not available.

Name and full (or relative) path of file (up to 260 characters). The extension of the file can be specified. By default, if the file extension is not specified, the external file will have no extension. A UNC path can be used.

Remark: If the external file already exists (same directory and same name), this file is destroyed and re-created. To avoid deleting an existing file, use fOpen associated with the foCreateIfNotExist constant.

This parameter can correspond to a full path or a path relative to the current directory (returned by fCurrentDir). This parameter is case-sensitive.
Reminder: In Android, an application has the rights to write into its setup directory or into one of its subdirectories, as well as onto the external memory (SDCard).

This parameter can correspond to a full path or a path relative to the current directory (returned by fCurrentDir). This parameter is case-sensitive.
Reminder: On iPhone/iPad, an application has the rights to write into its setup directory or into one of its subdirectories.

Options for file creation:

• Lock options: A lock can be implemented when the external file is opened:
  

  foAutomaticDeletion	The file is locked when opened, and will be automatically deleted when closed (when fClose is called, or when the application is closed). If multiple applications are using the file, it will be automatically deleted when the last application closes it (when fClose is called, or at the end of the application).
  foReadLock	The file will be created in read-only. The other applications that use this file will not be able to read it.
  foWriteLock	The file will be created in write-only. The other applications that use this file will not be able to modify it.

  
  The lock options are not available. The external file can be freely accessed by the other applications.

• Type of external file to create. This type is used by fReadLine and fWriteLine to define the type of information to read and write in the external file:
  

  foAnsi	Ansi file. This constant is used to manage an Ansi file when the "Use Unicode strings at runtime" mode is enabled in the project configuration. This mode is used by default in the WINDEV and WEBDEV projects.
  foUnicode	Unicode file. This constant is used to manage a Unicode file when the "Use Ansi strings at runtime" mode is enabled in the project configuration. This mode is used by default in WINDEV Mobile projects.

  
  
  New in version 28
  The constants for defining the file type are now available.
  The type of the file to be created is not available. The type of the file corresponds to the default mode.

By default, if no constant is specified:

• the external file can be freely accessed by the other applications,
• the type of the file corresponds to the default mode.