Wait for a BTC Mainnet Payment Event

SUBTC supports long polling to wait for a payment to arrive.
The wallet_wait_event endpoint blocks until the expected payment is detected or the timeout expires.

Command:

curl -sS -X POST "https://api.subtc.net/v1/btc?mode=wallet_wait_event" \
  -H "X-SUBTC-KEY: $KEY" \
  -H "Content-Type: application/json" \
  -d "{\"wallet_id\":\"$WID\",\"address\":\"$ADDR\",\"expected_sat\":20000,\"timeout_sec\":300}"

{
 "ok": true,
 "request_id": "f782b72d092c43a2",
 "result": {
  "address": "bc1q59ct7xwn0qa7kl722vdedaa2ajzkmmu78gm9jl",
  "coin": "btc",
  "net": "main",
  "expected_sat": 20000,
  "received_sat": 30000,
  "status": "confirmed",
  "wallet_id": "w_87d2a561cdd665948c1d756106f7b2179327927c3b8c"
 }
}

The API waited until the wallet address received at least **20,000 SAT**.

The detected payment was:

received_sat = 30,000 SAT
status = confirmed

This makes wallet_wait_event useful for synchronous payment flows where the server waits for confirmation before continuing.

API Base:
https://subtc.net/api