#include <sys/types.h>#include <sys/socket.h>	/* various networking crud */#include <netinet/in.h>#include <netinet/tcp.h>#include <netdb.h>#include <plan9.h> voidgetremotehostname(char *name, int nname){	struct sockaddr_in sock;	struct hostent *hp;	uint len;	int on; 	strecpy(name, name+nname, "unknown");	len = sizeof sock;	if(getpeername(0, (struct sockaddr*)&sock, (void*)&len) < 0)		return; 	hp = gethostbyaddr((char *)&sock.sin_addr, sizeof (struct in_addr),		sock.sin_family);	if(hp == 0)		return; 	strecpy(name, name+nname, hp->h_name);	on = 1;	setsockopt(0, SOL_SOCKET, SO_KEEPALIVE, (char*)&on, sizeof(on)); 	on = 1;	setsockopt(0, IPPROTO_TCP, TCP_NODELAY, (char*)&on, sizeof(on));}