SCTP一对一模式(TCP)模式的客户端代码

以下代码为基于sctp协议一对一模式(TCP)模式的客户端代码.

 #include <stdio.h>  #include <stdlib.h>  #include <string.h>  #include <unistd.h>  #include <sys/types.h>  #include <sys/socket.h>  #include <netinet/in.h>  #include <netinet/sctp.h>  #include <arpa/inet.h>    const int buf_size = 1024;  const int echo_port = 19000;    char *usage_msg = "usage echo_c ip_addr istreams ostream ochannel";  void usage()  {      fprintf(stderr,"%s\n", usage_msg);      exit(1);  }    int main(int argc, char** argv)  {      int sockfd, len;      struct sockaddr_in serv_addr;                       struct sctp_initmsg initmsg;      struct sctp_status status;      struct sctp_sndrcvinfo sinfo;      int ochannel;             if(argc < 5) usage();      sockfd = socket(AF_INET,SOCK_STREAM,IPPROTO_SCTP);      if(sockfd < 0)      {          printf("error while initializing socket.\n");          exit(1);      }        struct sockaddr_in *addrs = (struct sockaddr_in*) malloc(sizeof(struct sockaddr_in));      serv_addr.sin_family = AF_INET;      serv_addr.sin_addr.s_addr = inet_addr(argv[1]);      serv_addr.sin_port = htons(echo_port);            memcpy(addrs,&serv_addr,sizeof(struct sockaddr_in));      memset(&initmsg, 0, sizeof(initmsg));      initmsg.sinit_max_instreams = atoi(argv[2]);      initmsg.sinit_num_ostreams = atoi(argv[3]);      printf("asking for %d input stream, %d output stream.\n", initmsg.sinit_max_instreams,initmsg.sinit_num_ostreams);        int brst = setsockopt(sockfd, IPPROTO_SCTP,SCTP_INITMSG, &initmsg,sizeof(initmsg));      if(brst != 0)      {          printf("error while set socket option.\n");          exit(1);      }        brst = sctp_connectx(sockfd, (struct sockaddr*) addrs, 1);      if(brst < 0)      {          printf("can not connect to host.\n");          exit(1);      }            memset(&status,0,sizeof(status));      len = sizeof(status);      status.sstat_assoc_id = 1;        brst = getsockopt(sockfd, IPPROTO_SCTP,SCTP_STATUS,&status,(socklen_t*)&len);      if(brst < 0)      {          printf("error while geting socket option.\n");          exit(1);      }        printf("input stream:%d, output stream:%d\n", status.sstat_instrms,status.sstat_outstrms);        ochannel = atoi(argv[4]);      if(ochannel >= status.sstat_outstrms)      {          printf("writing on illegal channel %d \n", ochannel);      }       while(true)      {       bzero(&sinfo,sizeof(sinfo));printf("input a message: ");char buff[100];bzero(buff, 100);        scanf("%s", buff);                printf("input ochannel:");        scanf("%d", &ochannel);sinfo.sinfo_stream = ochannel;sctp_send(sockfd, buff, strlen(buff), &sinfo, 0);      }       close(sockfd);      return 0;  }  

以下代码为基于SCTP协议的一对一模式(TCP)模式的客户端代码。