daytimetcpcli2.lc

unix网络编程卷1：套接口API的全书源码

#include    "unp.h"##  1 ##src/names/daytimetcpcli2.c##

int##  2 ##src/names/daytimetcpcli2.c##
main(int argc, char **argv)##  3 ##src/names/daytimetcpcli2.c##
{##  4 ##src/names/daytimetcpcli2.c##
    int     sockfd, n;##  5 ##src/names/daytimetcpcli2.c##
    char    recvline[MAXLINE + 1];##  6 ##src/names/daytimetcpcli2.c##
    struct sockaddr_in servaddr;##  7 ##src/names/daytimetcpcli2.c##
    struct in_addr **pptr, *addrs[2];##  8 ##src/names/daytimetcpcli2.c##
    struct hostent *hp;##  9 ##src/names/daytimetcpcli2.c##
    struct servent *sp;## 10 ##src/names/daytimetcpcli2.c##

    if (argc != 3)## 11 ##src/names/daytimetcpcli2.c##
        err_quit("usage: daytimetcpcli2 <hostname> <service>");## 12 ##src/names/daytimetcpcli2.c##

    bzero(&servaddr, sizeof(servaddr));## 13 ##src/names/daytimetcpcli2.c##
    servaddr.sin_family = AF_INET;## 14 ##src/names/daytimetcpcli2.c##

    if (inet_pton(AF_INET, argv[1], &servaddr.sin_addr) == 1) {## 15 ##src/names/daytimetcpcli2.c##
        addrs[0] = &servaddr.sin_addr;## 16 ##src/names/daytimetcpcli2.c##
        addrs[1] = NULL;## 17 ##src/names/daytimetcpcli2.c##
        pptr = &addrs[0];## 18 ##src/names/daytimetcpcli2.c##
    } else if ((hp = gethostbyname(argv[1])) != NULL) {## 19 ##src/names/daytimetcpcli2.c##
        pptr = (struct in_addr **) hp->h_addr_list;## 20 ##src/names/daytimetcpcli2.c##
    } else## 21 ##src/names/daytimetcpcli2.c##
        err_quit("hostname error for %s: %s", argv[1], hstrerror(h_errno));## 22 ##src/names/daytimetcpcli2.c##

    if ((n = atoi(argv[2])) > 0)## 23 ##src/names/daytimetcpcli2.c##
        servaddr.sin_port = htons(n);## 24 ##src/names/daytimetcpcli2.c##
    else if ((sp = getservbyname(argv[2], "tcp")) != NULL)## 25 ##src/names/daytimetcpcli2.c##
        servaddr.sin_port = sp->s_port;## 26 ##src/names/daytimetcpcli2.c##
    else## 27 ##src/names/daytimetcpcli2.c##
        err_quit("getservbyname error for %s", argv[2]);## 28 ##src/names/daytimetcpcli2.c##

    for (; *pptr != NULL; pptr++) {## 29 ##src/names/daytimetcpcli2.c##
        sockfd = Socket(AF_INET, SOCK_STREAM, 0);## 30 ##src/names/daytimetcpcli2.c##

        memmove(&servaddr.sin_addr, *pptr, sizeof(struct in_addr));## 31 ##src/names/daytimetcpcli2.c##
        printf("trying %s\n", Sock_ntop((SA *) &servaddr, sizeof(servaddr)));## 32 ##src/names/daytimetcpcli2.c##

        if (connect(sockfd, (SA *) &servaddr, sizeof(servaddr)) == 0)## 33 ##src/names/daytimetcpcli2.c##
            break;              /* success */## 34 ##src/names/daytimetcpcli2.c##
        err_ret("connect error");## 35 ##src/names/daytimetcpcli2.c##
        close(sockfd);## 36 ##src/names/daytimetcpcli2.c##
    }## 37 ##src/names/daytimetcpcli2.c##
    if (*pptr == NULL)## 38 ##src/names/daytimetcpcli2.c##
        err_quit("unable to connect");## 39 ##src/names/daytimetcpcli2.c##

    while ((n = Read(sockfd, recvline, MAXLINE)) > 0) {## 40 ##src/names/daytimetcpcli2.c##
        recvline[n] = 0;        /* null terminate */## 41 ##src/names/daytimetcpcli2.c##
        Fputs(recvline, stdout);## 42 ##src/names/daytimetcpcli2.c##
    }## 43 ##src/names/daytimetcpcli2.c##
    exit(0);## 44 ##src/names/daytimetcpcli2.c##
}## 45 ##src/names/daytimetcpcli2.c##