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otxn_type ​

Summary. Return the transaction type (a TxType numeric code) of the originating transaction.

Signature.

c
int64_t otxn_type();

Parameters. None.

Return value. The transaction type as a non-negative integer — the same numeric codes listed in hook/tts.h, for example ttPAYMENT (0), ttESCROW_CREATE (1), ttHOOK_SET (22), ttURITOKEN_MINT (45), ttINVOKE (99). Does not return an error.

Common failure patterns.

  • None — it is a pure accessor. If you compare against the wrong constant set, note the codes are the tt* values from hook/tts.h, not the SField sfTransactionType field code.

Caveats / notes.

  • During a failed-emit callback the value comes from the emitted transaction's sfTransactionType (see The originating transaction).
  • Use the tt* constants from hook/tts.h rather than hard-coding integers where you can.

Minimal example.

c
int64_t tt = otxn_type();   // e.g. 0 for a Payment

Practical example (a payment filter, mirrors control.md's rollback example).

c
#define ttPAYMENT 0
int64_t hook(uint32_t reserved)
{
    _g(1, 1);
    // Reject anything that is not a Payment.
    if (otxn_type() != ttPAYMENT)
        rollback(SBUF("only payments accepted"), __LINE__);
    accept(SBUF("payment ok"), 0);
}

Related APIs. otxn_field, otxn_id; tx-type constants in hook/tts.h.