将客户端连接到 TCP/IP 服务器时出错

无法在 Linux Mint 上通过 tcp/ip 在服务器和客户端之间创建连接。通过 gcc.Connect 编译返回 -1 并且 errno 给出 ECONNREFUSED。之前这个服务器只在 Windows 上使用 winsock2 编写。服务器

#include <sys/types.h>
#include <sys/socket.h>
#include <sys/signal.h>
#include <sys/wait.h>
#include <sys/resource.h>
#include <netinet/in.h>

#include <iostream>
#include <unistd.h>
#include <iomanip>
#include <string.h>
using namespace std;

int main()
{
    int s,s2,bl;
    s=socket(AF_INET,SOCK_STREAM,0);
    struct sockaddr_in local;
    local.sin_port=htonl(7500);
    local.sin_family=AF_INET;
    local.sin_addr.s_addr=htonl(INADDR_ANY);
    bl=bind(s,(struct sockaddr*)&local,sizeof(local));
    cout<<"Listen\n";
    bl=listen(s,5);
    cout<<"Accept\n";
    s2=accept(s,0,0);
    send(s2,"HW",sizeof("HW"),0);
}

客户

#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <netinet/in.h>

#include <iostream>
#include <unistd.h>
#include <iomanip>
#include <string.h>
using namespace std;
int main()
{
    int s,rc;
    s=socket(AF_INET,SOCK_STREAM,0);
    struct sockaddr_in peer;
    peer.sin_family=AF_INET;
    peer.sin_port=htons(7500);
    peer.sin_addr.s_addr=inet_addr("127.0.0.1");
    cout<<"Connecting\n";
    rc=connect(s,(struct sockaddr*)&peer,sizeof(peer));
    switch (errno)
    {
    case EACCES:
        fprintf(stdout, "EACCESS");
        break;
    case EPERM:
        fprintf(stdout, "EPERM");
        break;
    case EADDRINUSE:
        fprintf(stdout, "EADDRINUSE");
        break;
    case EAFNOSUPPORT:
        fprintf(stdout, "EAFNOSUPPORT");
        break;
    case EAGAIN:
        fprintf(stdout, "EAGAIN");
        break;
    case EALREADY:
        fprintf(stdout, "EALREADY");
        break;
    case EBADF:
        fprintf(stdout, "EBADF");
        break;
    case ECONNREFUSED:
        fprintf(stdout, "ECONNREFUSED");
        break;
    case EFAULT:
        fprintf(stdout, "EFAULT");
        break;
    case EINPROGRESS:
        fprintf(stdout, "EINPROGRESS");
        break;
    case EINTR:
        fprintf(stdout, "EINTR");
        break;
    case EISCONN:
        fprintf(stdout, "EISCONN");
        break;
    case ENETUNREACH:
        fprintf(stdout, "ENETUNREACH");
        break;
    case ENOTSOCK:
        fprintf(stdout, "ENOTSOCK");
        break;
    case ETIMEDOUT:
        fprintf(stdout, "ETIMEDOUT");
        break;
    default:
        fprintf(stdout, "unknown error(%d)", errno);
        break;
    }
    cout<<endl;
    char choice[100];
    char buf[100];
    recv(s,buf,sizeof("HW"),0);
}