A pathname inside the resource
a location to place the length of the contents of the file, or NULL if the length is not needed
a location to place the flags about the file, or NULL if the length is not needed
TRUE if the file was found. FALSE if there were errors
GException on failure.
2.32
Looks for a file at the specified path in the resource and if found returns information about it.
lookup_flags controls the behaviour of the lookup.