Tries to guess the type of content stored on this.
Returns one or more textual identifiers of well-known content types (typically prefixed with "x-content/"), e.g. x-content/image-dcf for camera memory cards. See the shared-mime-info specification for more on x-content types.
This is an asynchronous operation (see guess_content_type_sync
for the synchronous version), and is finished by calling guess_content_type.end with the
this and AsyncResult data returned in the
callback.
| this |
a Mount |
| force_rescan |
Whether to force a rescan of the content. Otherwise a cached result will be used if available |
| cancellable |
optional Cancellable object, null to ignore |
| callback | |
| user_data |
user data passed to |