add SendQ TrySend() TryRecv(); handle re-register.

lichao

2021-04-14 aa1542b6d6a4680088ac715c4ce40f97ada554fb

 src/bh_api.h

@@ -64,8 +64,7 @@

bool BHSendReply(BHSrcInfo *src,
                 const void *reply,
                 const int reply_len,
                 const int timeout_ms);
                 const int reply_len);

// int BHCleanUp();