import socket,os,hashlibserver=socket.socket()server.bind(("localhost",9999))#绑定要监听的端口server.listen()#开始监听while True:    conn,addr=server.accept()#等待用户输入命令    print("newconn",addr)    while True:        print("等待新指令")        data=conn.recv(1024)        if not data:            print("客户端断开")            break        cmd,filename=data.decode().split()        print(filename)        if os.path.isfile(filename):            f = open(filename,"rb")            m = hashlib.md5()            file_size=os.stat(filename).st_size            conn.send(str(file_size).encode())#send file size            conn.recv(1024)#wait for ack            for line in f:                m.update(line)                conn.send(line)            print("file md5",m.hexdigest())            f.close()            conn.send(m.hexdigest().encode())#send md5        print("send done")server.close()

import socket,os,hashlibclient=socket.socket()client.connect(("localhost",9999))while True:    cmd = input(">>:".strip())    if len(cmd) ==0:continue    if cmd.startswith("get"):        client.send(cmd.encode())        server_respose=client.recv(1024)#文件大小        print("server respose",server_respose)        client.send(b"ready to  recv file")        file_total_size = int(server_respose.decode())        received_size=0        filename=cmd.split()[1]        f = open(filename+".new","wb")#复制新文件        m = hashlib.md5()        while received_size<file_total_size:            if file_total_size - received_size > 1024:#接收不止一次                size=1024            else:#最后一次接收                size=file_total_size-received_size                print("last receive",size)            data=client.recv(size)            received_size+=len(data)            m.update(data)            f.write(data)    else:        new_file_md5=m.hexdigest()        print("file recv done",received_size,file_total_size)        f.close()    server_file_md5=client.recv(1024)#最后接收服务器返回的md5    print("server file md5",server_file_md5)    print("client file md5",new_file_md5)client.close