#include <string.h>#include <stdio.h>#include <sys/types.h>#include <sys/socket.h>#include <netdb.h>#include <unistd.h> intdial(const char *s){	struct addrinfo *r, *a, hint = {.ai_flags = AI_ADDRCONFIG, .ai_family = AF_UNSPEC, 0};	char host[128], *port;	int e, f; 	if(strncmp(s, "udp!", 4) == 0){		hint.ai_socktype = SOCK_DGRAM;		hint.ai_protocol = IPPROTO_UDP;	}else if(strncmp(s, "tcp!", 4) == 0){		hint.ai_socktype = SOCK_STREAM;		hint.ai_protocol = IPPROTO_TCP;	}else{		fprintf(stderr, "invalid dial string: %s\n", s);		return -1;	}	if((port = strchr(s+4, '!')) == NULL){		fprintf(stderr, "invalid dial string: %s\n", s);		return -1;	}	if(snprintf(host, sizeof(host), "%.*s", (int)(port-s-4), s+4) >= (int)sizeof(host)){		fprintf(stderr, "host name too large: %s\n", s);		return -1;	}	port++;	if((e = getaddrinfo(host, port, &hint, &r)) != 0){		fprintf(stderr, "%s: %s\n", gai_strerror(e), s);		return -1;	}	f = -1;	for(a = r; a != NULL; a = a->ai_next){		if((f = socket(a->ai_family, a->ai_socktype, a->ai_protocol)) < 0)			continue;		if(connect(f, a->ai_addr, a->ai_addrlen) == 0)			break;		close(f);		f = -1;	}	freeaddrinfo(r); 	return f;}