function nprpcProbeStreamInit

Swift

func nprpcProbeStreamInit(body: @escaping @Sendable () async throws -> Void, installFirstAccess: (@escaping @Sendable () -> Void) -> Void) -> StreamInitProbeResult

Runs body and waits until either the first stream access (via installFirstAccess) or an init-time throw / clean return.

Wire installFirstAccess to reader.onFirstAccess = fn.

nprpc_swift/Sources/NPRPC/StreamReader.swift:585