Opens a file for reading. The result is a GFileInputStream that
can be used to read the contents of the file.
If cancellable is not NULL, then the operation can be cancelled by
triggering the cancellable object from another thread. If the operation
was cancelled, the error G_IO_ERROR_CANCELLED will be returned.
If the file does not exist, the G_IO_ERROR_NOT_FOUND error will be
returned. If the file is a directory, the G_IO_ERROR_IS_DIRECTORY
error will be returned. Other errors are possible too, and depend
on what kind of filesystem the file is on.
Virtual: read_fn
Opens a file for reading. The result is a GFileInputStream that can be used to read the contents of the file. If cancellable is not NULL, then the operation can be cancelled by triggering the cancellable object from another thread. If the operation was cancelled, the error G_IO_ERROR_CANCELLED will be returned. If the file does not exist, the G_IO_ERROR_NOT_FOUND error will be returned. If the file is a directory, the G_IO_ERROR_IS_DIRECTORY error will be returned. Other errors are possible too, and depend on what kind of filesystem the file is on. Virtual: read_fn