udp_connect.lc

unix网络编程卷1：套接口API的全书源码

/* include udp_connect */
#include    "unp.h"##  1 ##src/lib/udp_connect.c##

int##  2 ##src/lib/udp_connect.c##
udp_connect(const char *host, const char *serv)##  3 ##src/lib/udp_connect.c##
{##  4 ##src/lib/udp_connect.c##
    int     sockfd, n;##  5 ##src/lib/udp_connect.c##
    struct addrinfo hints, *res, *ressave;##  6 ##src/lib/udp_connect.c##

    bzero(&hints, sizeof(struct addrinfo));##  7 ##src/lib/udp_connect.c##
    hints.ai_family = AF_UNSPEC;##  8 ##src/lib/udp_connect.c##
    hints.ai_socktype = SOCK_DGRAM;##  9 ##src/lib/udp_connect.c##

    if ((n = getaddrinfo(host, serv, &hints, &res)) != 0)## 10 ##src/lib/udp_connect.c##
        err_quit("udp_connect error for %s, %s: %s",## 11 ##src/lib/udp_connect.c##
                 host, serv, gai_strerror(n));## 12 ##src/lib/udp_connect.c##
    ressave = res;## 13 ##src/lib/udp_connect.c##

    do {## 14 ##src/lib/udp_connect.c##
        sockfd = socket(res->ai_family, res->ai_socktype, res->ai_protocol);## 15 ##src/lib/udp_connect.c##
        if (sockfd < 0)## 16 ##src/lib/udp_connect.c##
            continue;           /* ignore this one */## 17 ##src/lib/udp_connect.c##

        if (connect(sockfd, res->ai_addr, res->ai_addrlen) == 0)## 18 ##src/lib/udp_connect.c##
            break;              /* success */## 19 ##src/lib/udp_connect.c##

        Close(sockfd);          /* ignore this one */## 20 ##src/lib/udp_connect.c##
    } while ((res = res->ai_next) != NULL);## 21 ##src/lib/udp_connect.c##

    if (res == NULL)            /* errno set from final connect() */## 22 ##src/lib/udp_connect.c##
        err_sys("udp_connect error for %s, %s", host, serv);## 23 ##src/lib/udp_connect.c##

    freeaddrinfo(ressave);## 24 ##src/lib/udp_connect.c##

    return (sockfd);## 25 ##src/lib/udp_connect.c##
}## 26 ##src/lib/udp_connect.c##
/* end udp_connect */

int## 27 ##src/lib/udp_connect.c##
Udp_connect(const char *host, const char *serv)## 28 ##src/lib/udp_connect.c##
{## 29 ##src/lib/udp_connect.c##
    int     n;## 30 ##src/lib/udp_connect.c##

    if ((n = udp_connect(host, serv)) < 0) {## 31 ##src/lib/udp_connect.c##
        err_quit("udp_connect error for %s, %s: %s",## 32 ##src/lib/udp_connect.c##
                 host, serv, gai_strerror(-n));## 33 ##src/lib/udp_connect.c##
    }## 34 ##src/lib/udp_connect.c##
    return (n);## 35 ##src/lib/udp_connect.c##
}## 36 ##src/lib/udp_connect.c##