Connect: Socket operation on non-socket

I see the problem. It’s this line:

if ( (sockfd = socket(AF_INET, SOCK_STREAM, 0) == -1))

The == operator has precedence over the = operator. Look at the way you have the parentheses structured on that expression a bit more carefully to see what I mean. sockfd is getting initialize to “0” as a result of being assigned a boolean expression (socket(…) == -1).

Change the socket initialization to this:

  for (i = 0; host->h_addr_list[i]; i++) 

    sockfd = socket(AF_INET, SOCK_STREAM, 0);
    if (sockfd == -1)
        printf("socket error\n");

Or if you prefer the “assign and compare” on the same line approach, you can probably say this:

if ( (sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1)

Notice the subtle difference.

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