add async recv suport; sync by waiting for async.

lichao

2021-03-31 3c2b6739208d961cf8b86460d7f05516d044960c

 src/center.cpp

@@ -23,7 +23,6 @@

SharedMemory &BHomeShm()
{
   static SharedMemory shm("bhome_default_shm_v0", 1024*1024*64);
   static SharedMemory shm("bhome_default_shm_v0", 1024 * 1024 * 64);
   return shm;
}