Oct 29, 2019 · Some socket gurus might know a direct way to set it. But it's easier to just query the system for it. This will correctly set both "flowinfo" and "scope_id" for you.

May 18, 2011 · I want to set sin6_addr byte order of sockaddr_in6 structure. For 16 bits or 32 bits variables, it is simple: Using htons or htonl: // IPv4 sockaddr_in addr; addr.sin_port = htons(123); addr.sin_addr.s_addr = htonl(123456); But for 128 bits variables, I dont know how to set byte order to network byte order:

Nov 29, 2011 · This will take the worry about sin6_scope_id from you; which is normally 0, except if you have link-local addresses like fe80::1234:56ff:fe78:9abc%eth2. This eth2 is converted to the correct scope ID. sin6_flowinfo is obsolete (AFAIK) and thus set to 0 in your resulting struct addrinfo's ai_addr.

So, basically the title says it all. I've been porting my unix socket C code to Windows, and apparently those structures do not have sin_len or sin6_len in windows. I'm using a union between sockaddr_storage, sockaddr_in and sockaddr_in6 everywhere, and just using the correct member according to ss_family.

Apr 26, 2010 · inet_ntoa() works for IPv4; inet_ntop() works for both IPv4 and IPv6. Given an input struct sockaddr *res, here are two snippets of code (tested on macOS):

Sep 3, 2019 · If I am using the struct sockaddr_in, the address family is already specified in any sockets I create. Furthermore,it seems redundant to use the sin_family member if it must always be AF_IN

Jun 27, 2012 · const uint8_t *bytes = ((const struct sockaddr_in6 *)addrPtr)->sin6_addr.s6_addr; Then add 12 to the pointer because the 12 first bytes are not interesting (10 0x00, then 2 0xff). Only the 4 last ones mater. bytes += 12; Now, we can use those four bytes to do whatever we want. For example, we might store them into a IPv4 struct in_addr address.

Apr 26, 2012 · The mapping of sin6_scope_id to an interface or set of interfaces is left to implementation and future specifications on the subject of site identifiers. So this field is entirely implementation specific. If you want this field to be filled in correctly, and your code should be as cross-platform as possible, you should use getaddrinfo():

Sep 4, 2019 · Below is an extract of example code for IPv6 and IPv4 clinet code: IPv6 int s; struct sockaddr_in6 addr; s = socket(AF_INET6, SOCK_STREAM, 0); addr.sin6_family = AF_INET6; addr.sin6_port = htons...

Feb 15, 2019 · Similarly, the variables inside sockaddr_in6 all start with the prefix sin6_, and the variables inside sockaddr start with the prefix sa_, and so on. in is presumably shorthand for "internet". Share