Sunday, August 7, 2011

Broken pipe on write

This one puzzled me for a bit. I opened a socket, bound it to a local interface alias address, called connect to a remote machine. Everything was fine. No errors, errno = 0. Then I called write on the socket and it says: "broken pipe". It seems that the cause was that I forgot to set the family for the call to connect:

struct sockaddr_in servaddr;
servaddr.sin_family = AF_INET;
servaddr.sin_port = htons( atoi(serv) );
if ( !inet_pton(AF_INET, host, &servaddr.sin_addr) )
 printf("inet_pton failed\n");
 rc = -1;
else if ( connect(fd,(const struct sockaddr *)&servaddr, 
    sizeof(servaddr)) == 0 )
    // return connected socket
    rc = fd;

So I thought I'd file this one for reference, in case I get it again. It's amazing how a simple typo can get you into so much trouble.