struct error

After the binary data is displayed using the package struct.pack 0

 

 

print (len (jdata)) 

hundred struct.pack = ( "i", only (jdata)) 
print (hundred) # 0

　　

64  
b'@\x00\x00\x00' 

　　This problem occurs while True service loop has two ends, resulting in multiple data received, after receiving the second received data results in zero, the solution: only one set while loop