The OpenTag Filedata ALP is an implementation of the Filedata ALP specified in DASH7 Mode 2. Therefore, it is also an official component of the OpenTag ALP API, and it is usable in the same ways as any other ALP. The Filedata ALP is also directly linked to the Veelite Module, so in the same way that session, system, and query ALP commands are equivalents to OTAPI functions, Filedata ALP commands are equivalents to Veelite functions.
The OpenTag Filedata ALP is a direct implementation of the Filedata ALP specified in DASH7 Mode 2. The message/protocol components used for OpenTag should match the values defined in the DASH7 spec. If using the Filedata ALP over MPipe, you should additionally make sure that NDEF protocol header fields are used.
The OpenTag Filedata ALP is implemented in OTlib/alp_filedata.c, and the calls in alp_filedata.c go mainly to the Veelite Module. As with all ALPs, messages/frames containing Filedata ALP information are first processed by the main ALP processor (alp_proc()) in OTlib/alp_main.c and then subsequently passed to the alp_filedata.c processor. Users should call alp_proc() in alp_main.c, after having stored a filedata ALP message in a Queue. alp_proc() will also be called automatically if the message has been passed through MPipe/NDEF or DASH7, so users probably never need to call alp_proc() at all unless implementing a generic interprocess API pipe.
void alp_proc(alp_record* in_rec, alp_record* out_rec, Queue* in_q, Queue* out_q, id_tmpl* user_id)
The filedata processor function (below) is implemented in alp_filedata.c and it is the only function that is public to the user. That said, it probably should never be called directly, as alp_proc() will call it when a valid Filedata ALP message is passed into alp_proc().
void alp_proc_filedata(alp_record* in_rec, alp_record* out_rec, Queue* in_q, Queue* out_q, id_tmpl* user_id)