connect() fails?

[Daniel Ng]

Hi,

I'm using uClibc 0.9.28 in a buildroot environment.

I'm having trouble connecting to a TCP socket. connect() returns -1 with errno 
set to '1' which from looking at the errno include files translates 
to 'EPERM'. 

According to the man page for connect(), this means I was trying to either 
connect to a broadcast address, or connect() was being blocked by a local 
firewall rule. I know I'm not using a broadcast address (it's 127.0.0.1), and 
I have no firewalls on my embedded platform. I can connect to the telnet 
server using the standard linux telnet client. Changing the FD flags makes no 
difference.

Any suggestions would be most helpful, short of upgrading uClibc.

Cheers,
Daniel


Here's the code-

struct addrinfo hints;

  struct addrinfo *res;

  const char *hostname = "localhost";

  const char *service  = TELNET_PORT;

  char buf[BUF_LEN];

  char stringError[ERROR_LEN];

  long flags        = 0;

  int fd            = 0;

  int connectResult = 0;

  int error         = 0;

 

  if(memset(stringError, 0, ERROR_LEN) == NULL)

  {

    Dprintf("ERROR: memset(stringError) returned Null Pointer\n"); 

    return -1;

  }

  

  if(memset(&hints, 0, sizeof(hints)) == NULL)

  {

    Dprintf("ERROR: memset(hints) returned Null Pointer\n"); 

    return -1;

  }

  hints.ai_socktype = SOCK_STREAM; // Telnet uses TCP

  hints.ai_family   = AF_INET;

      

  if ( (error = getaddrinfo(hostname, service, &hints, &res)) != 0 ) 

  {

    Dprintf("ERROR: getaddrinfo() returned error: %d\n", error); 

    return -1;

  }  

  

  if ( (fd = socket(res->ai_family, res->ai_socktype, res->ai_protocol)) < 0 )

  {

    Dprintf("ERROR: socket() returned error: %d- %s\n", 

            fd, strerror_r(errno,stringError,ERROR_LEN)); 

    return -1;

  }

  

  if ( fcntl(fd, F_GETFL, flags) < 0 )

  {

    Dprintf("ERROR: fcntl(F_GETFL) returned error: %d- %s\n", 

            fd, strerror_r(errno,stringError,ERROR_LEN)); 

    return -1;

  }

  

  flags |= (O_NONBLOCK|O_ASYNC);

     

  if ( fcntl( fd, F_SETFL, flags ) < 0 )

  {

    Dprintf("ERROR: fcntl(F_SETFL) returned error: %d- %s\n", 

            fd, strerror_r(errno,stringError,ERROR_LEN)); 

    return -1;

  }

    

  if ( (connectResult = connect(fd, res->ai_addr, res->ai_addrlen)) < 0 )

  {

    if (errno != EINPROGRESS)

    {

      Dprintf("ERROR: connect() returned error: %d- %s\n", 

              connectResult, strerror_r(errno,stringError,ERROR_LEN)); 

      return -1;

    }

    else

    {

      ;

      // Check connect() succeeded in this case?

      // If connect fails then nothing else will work anyway.

    }

  }

    

  freeaddrinfo(res);