const char * vortex_frame_mime_header_name ( VortexMimeHeader header  ) 

Provided a reference to a MIME header VortexMimeHeader, the function allows to get the MIME header field name.

Parameters:
header The header where the operation will be performed.
Returns:
A reference to the MIME header field name or NULL if it fails. The function can only fail if the header reference received is NULL.