slot_type

Summary. Return the field type of a slotted object, or (with a flag) whether a slotted amount is native XAH.

Signature.

int64_t slot_type(uint32_t slot_no, uint32_t flags);

Parameters.

Name	Type	Description
slot_no	uint32_t	Slot to inspect.
flags	uint32_t	0 = return the field code; 1 = amount-native check (see below).

Return value. Behaviour depends on flags:

• flags == 0 — returns the slot's field code, (type << 16) | index (the fieldCode of the field's SField).

• flags == 1 — the slot must hold an STI_AMOUNT; returns 1 if the amount is native (XAH) and 0 if it is an IOU. If the slot is not an amount, returns NOT_AN_AMOUNT (-32).

Errors for both modes: DOESNT_EXIST (-5) if the slot is empty; INTERNAL_ERROR (-2) if corrupt; INVALID_ARGUMENT (-7) if flags is neither 0 nor 1.

Common failure patterns.

• Using flags == 1 on a non-amount slot → NOT_AN_AMOUNT.
• Passing a flags value other than 0 or 1 → INVALID_ARGUMENT.

Caveats / notes.

• The flags == 0 return is a field code, so you can compare it against sf* constants to learn what a slotted field is before reading it.
• Use flags == 1 to branch between XAH and IOU handling before calling slot_float.

Minimal example.

int64_t is_xrp = slot_type(amt_slot, 1);   // 1 = XAH, 0 = IOU

Related APIs. slot_float, slot_subfield.