Function aeron_archive_persistent_subscription_context_set_start_position 

pub unsafe extern "C" fn aeron_archive_persistent_subscription_context_set_start_position(
    context: *mut aeron_archive_persistent_subscription_context_t,
    start_position: i64,
) -> c_int

Set the position to start the subscription from, can be an actual position or AERON_ARCHIVE_PERSISTENT_SUBSCRIPTION_FROM_START or AERON_ARCHIVE_PERSISTENT_SUBSCRIPTION_FROM_LIVE.

@param context to configure. @param start_position the position to start the subscription from. @return 0 on success, -1 on error.