Espressif Systems ESP8266EX - Page 27

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3. Sample Codes
󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧}
󰲧󰲧󰲧󰲧}while(ret󰲧!=󰲧0);
󰲧󰲧󰲧󰲧printf("ESP8266󰲧TCP󰲧server󰲧task󰲧>󰲧listen󰲧ok\n”);
Wait until the TCP client is connected to the server; then start receiving data packets
when the TCP communication is established:
󰲧󰲧󰲧󰲧int32󰲧client_sock;
󰲧󰲧󰲧󰲧int32󰲧len󰲧=󰲧sizeof(struct󰲧sockaddr_in);
󰲧󰲧󰲧󰲧for󰲧(;;)󰲧{
󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧printf("ESP8266󰲧TCP󰲧server󰲧task󰲧>󰲧wait󰲧client\n”);
󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧/*block󰲧here󰲧waiting󰲧remote󰲧connect󰲧request*/
󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧if󰲧((client_sock󰲧=󰲧accept(listenfd,󰲧(struct󰲧sockaddr󰲧*)&remote_addr,󰲧(socklen_t󰲧
*)&len))󰲧<󰲧0)󰲧{
󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧printf("ESP8266󰲧TCP󰲧server󰲧task󰲧>󰲧accept󰲧fail\n");
󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧continue;
󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧}
󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧printf("ESP8266󰲧TCP󰲧server󰲧task󰲧>󰲧Client󰲧from󰲧%s󰲧%d\n",󰲧
inet_ntoa(remote_addr.sin_addr),󰲧htons(remote_addr.sin_port));
󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧char󰲧*recv_buf󰲧=󰲧(char󰲧*)zalloc(128);
󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧while󰲧((recbytes󰲧=󰲧read(client_sock󰲧,󰲧recv_buf,󰲧128))󰲧>󰲧0)󰲧{
󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧recv_buf[recbytes]󰲧=󰲧0;
󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧printf("ESP8266󰲧TCP󰲧server󰲧task󰲧>󰲧read󰲧data󰲧success󰲧%d!\nESP8266󰲧TCP󰲧server󰲧task󰲧
>󰲧%s\n",󰲧recbytes,󰲧recv_buf);
󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧}
󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧free(recv_buf);
󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧if󰲧(recbytes󰲧<=󰲧0)󰲧{
󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧printf("ESP8266󰲧TCP󰲧server󰲧task󰲧>󰲧read󰲧data󰲧fail!\n");
󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧close(client_sock);
󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧}
󰲧󰲧󰲧󰲧}
2. Compile the application program, generate firmware and download it into the ESP8266
module.
3. Power off the module, and change it to operation mode; then power on the module and
run the program.
4. Establish a TCP client using the network debugging tool, then connect the TCP client
with the ESP8266 TCP server, and start sending data.
Espressif
! /!23 37
2017.05