| name | socket-programming |
| description | Low-level socket programming including BSD sockets, Winsock, and network byte manipulation |
| sasmp_version | 1.3.0 |
| version | 2.0.0 |
| bonded_agent | 02-networking-specialist |
| bond_type | SECONDARY_BOND |
| parameters | [object Object] |
| retry_config | [object Object] |
| observability | [object Object] |
Socket Programming for Games
Master low-level socket programming for custom game networking.
Socket Types
| Type |
Protocol |
Use Case |
| SOCK_STREAM |
TCP |
Reliable data |
| SOCK_DGRAM |
UDP |
Real-time |
| SOCK_RAW |
Raw IP |
Custom protocols |
BSD Socket (C)
#include <sys/socket.h>
#include <netinet/in.h>
int create_game_server(int port) {
int sockfd = socket(AF_INET, SOCK_DGRAM, 0);
struct sockaddr_in addr = {
.sin_family = AF_INET,
.sin_port = htons(port),
.sin_addr.s_addr = INADDR_ANY
};
bind(sockfd, (struct sockaddr*)&addr, sizeof(addr));
fcntl(sockfd, F_SETFL, O_NONBLOCK);
return sockfd;
}
Socket Options
// Disable Nagle (reduce latency)
int flag = 1;
setsockopt(sockfd, IPPROTO_TCP, TCP_NODELAY, &flag, sizeof(flag));
// Enable address reuse
setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &flag, sizeof(flag));
// Set buffer size
int bufsize = 65536;
setsockopt(sockfd, SOL_SOCKET, SO_RCVBUF, &bufsize, sizeof(bufsize));
Byte Order
// Network byte order
uint16_t port_net = htons(8080);
uint32_t ip_net = htonl(ip_host);
// Host byte order
uint16_t port_host = ntohs(port_net);
Platform Differences
| Feature |
BSD |
Winsock |
| Init |
None |
WSAStartup() |
| Close |
close() |
closesocket() |
| Error |
errno |
WSAGetLastError() |
| Non-block |
fcntl() |
ioctlsocket() |
Troubleshooting
Common Failure Modes
| Error |
Root Cause |
Solution |
| EADDRINUSE |
Port in use |
SO_REUSEADDR |
| ECONNRESET |
Peer closed |
Handle gracefully |
| EMFILE |
Too many fds |
Increase ulimit |
| High latency |
Nagle |
TCP_NODELAY |
Debug Checklist
# Check listening sockets
netstat -tlnp | grep game-server
# Trace syscalls
strace -e socket,bind,connect ./game-server
# Monitor traffic
tcpdump -i lo port 8080
Unit Test Template
void test_socket_creation() {
int fd = create_game_server(8080);
assert(fd >= 0);
struct sockaddr_in addr;
socklen_t len = sizeof(addr);
getsockname(fd, (struct sockaddr*)&addr, &len);
assert(ntohs(addr.sin_port) == 8080);
close(fd);
}
Resources
assets/ - Socket templatesreferences/ - Platform guides