抽象名前空間でソケットを機能させるための鍵は、'bind' および 'connect' コマンドに適切な長さを提供することです。sockaddr_un のアドレスの末尾に '\0' を設定しないようにするには、strncpy などでコピーする必要があります。
Pawelの回答ですでに説明されているので、例を挙げます。
サーバ：
int main(int argc, char** argv)
{
//to remove warning for unused variables.
int dummy = argc;
dummy = (int)argv;
int fdServer = 0;
int fdClient = 0;
int iErr = 0;
int n = 0;
socklen_t addr_len = 0;
char buff[1024];
char resp[1024];
const char* const pcSocketName = "/tmp/test";
struct sockaddr_un serv_addr;
//set the structure with 'x' instead of 0 so that we're able
//to see the full socket name by 'cat /proc/net/unix'
//you may try playing with addr_len and see the actual name
//reported in /proc/net/unix
memset(&serv_addr, 'x', sizeof(serv_addr));
serv_addr.sun_family = AF_UNIX;
serv_addr.sun_path[0] = '\0';
//sizeof(pcSocketName) returns the size of 'char*' this is why I use strlen
strncpy(serv_addr.sun_path+1, pcSocketName, strlen(pcSocketName));
fdServer = socket(PF_UNIX, SOCK_STREAM, 0);
if(-1 == fdServer) {
printf("socket() failed: [%d][%s]\n", errno, strerror(errno));
return(-1);
}
iErr = bind(fdServer, (struct sockaddr*)&serv_addr, offsetof(struct sockaddr_un, sun_path) + 1/*\0*/ + strlen(pcSocketName));
if(0 != iErr) {
printf("bind() failed: [%d][%s]\n", errno, strerror(errno));
return(-1);
}
iErr = listen(fdServer, 1);
if(0 != iErr) {
printf("listen() failed: [%d][%s]\n", errno, strerror(errno));
return(-1);
}
addr_len = sizeof(pcSocketName);
while(1) {
fdClient = accept(fdServer, (struct sockaddr*) &serv_addr, &addr_len);
if(0 >= fdClient) {
printf("accept() failed: [%d][%s]\n", errno, strerror(errno));
return(-1);
}
memset(resp, 0, sizeof(resp));
memset(buff, 0, sizeof(buff));
n = recv(fdClient, buff, sizeof(buff), 0);
if(0 > n) {
printf("recv() failed: [%d][%s]\n", errno, strerror(errno));
return(-1);
}
printf("[client]: %s\n", buff);
sprintf(resp, "echo >> %s", buff);
n = send(fdClient, resp, sizeof(resp), 0);
if(0 > n) {
printf("send() failed: [%d][%s]\n", errno, strerror(errno));
return(-1);
}
printf("[server]: %s\n", resp);
}
close(fdServer);
return(0);
}
クライアント：
int main(int argc, char** argv) {
//to remove warning for unused variables.
int dummy = argc;
dummy = (int)argv;
int fdClient = 0;
struct sockaddr_un serv_addr;
int iErr = 0;
const char* const pcSocketName = "/tmp/test";
char buff[1024];
memset(&serv_addr, 0, sizeof(serv_addr));
serv_addr.sun_family = AF_UNIX;
serv_addr.sun_path[0] = '\0';
strncpy(serv_addr.sun_path+1, pcSocketName, strlen(pcSocketName));
fdClient = socket(PF_UNIX, SOCK_STREAM, 0);
if(-1 == fdClient) {
printf("socket() failed: [%d][%s]\n", errno, strerror(errno));
return(-1);
}
iErr = connect(fdClient, (struct sockaddr*) &serv_addr, offsetof(struct sockaddr_un, sun_path) + 1/*\0*/ + strlen(pcSocketName));
if(0 != iErr) {
printf("connect() failed: [%d][%s]\n", errno, strerror(errno));
return(-1);
}
memset(buff, 0, sizeof(buff));
sprintf(buff, "Hello from client!");
printf("[client]: %s\n", buff);
iErr = send(fdClient, buff, sizeof(buff), 0);
if(0 > iErr){
printf("write() failed: [%d][%s]\n", errno, strerror(errno));
return(-1);
}
iErr = recv(fdClient, buff, sizeof(buff), 0);
if(0 > iErr){
printf("read() failed: [%d][%s]\n", errno, strerror(errno));
return(-1);
}
printf("[server]: %s\n", buff);
return(0);
}