Asynchronous operations

Building a shielded transaction involves note selection and zero-knowledge proving, which takes real time — so the sending RPC methods do not block. Methods such as z_sendmany and z_shieldcoinbase validate their arguments, start the work in the background, and immediately return an operation id (e.g. opid-...).

Clients then follow the same lifecycle zcashd used:

1. Poll with z_getoperationstatus [["opid-..."]] — returns the current state (executing, success, failed) without consuming it.
2. Collect with z_getoperationresult [["opid-..."]] — returns the outcome of finished operations and removes them: the result value on success (for sends, the transaction ids), or an error object on failure.
3. z_listoperationids lists the operations the wallet currently knows about.

Operations are held in memory, not in the wallet database — do not expect an operation id to survive a wallet restart. If you lose track of a send, check z_listtransactions / z_viewtransaction to see whether the transaction was created and broadcast.