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From: dave jones <s.dave.jones@gmail.com>
To: freebsd-net@freebsd.org
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Subject: UDP socket disconnect problem
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Hello,

In Linux, I can disconnect the socket using:
sa.sin_family = AF_UNSPEC;
val = connect(sockfd, (struct sockaddr *)&sa, sizeof(sa));

the return value of val is 0; on freebsd, the return value of connect() is -1.
According to Linux's connect(2) man page:

Connectionless sockets may dissolve
the association by connecting to an address with the  sa_family  member
of sockaddr set to AF_UNSPEC

but FreeBSD's connect says:
Datagram sockets may dissolve the association by connecting
 to an invalid address, such as a null address.

I try to convert above code to
memset(&sa, 0, sizeof(sa));
sa.sin_addr.s_addr = htonl(INADDR_ANY);
val = connect(sockfd, (struct sockaddr *)&sa, sizeof(sa));

the return value of val still -1. Any idea? Thanks.

Regards,
Dave.