Message 332391 - Python tracker (original) (raw)

#include <netinet6/in6.h> in the macOS 10.14 SDK says:

/*

• RFC 3542 define the following socket options in a manner incompatible
• with RFC 2292:
• IPV6_PKTINFO
• IPV6_HOPLIMIT
• IPV6_NEXTHOP
• IPV6_HOPOPTS
• IPV6_DSTOPTS
• IPV6_RTHDR
• To use the new IPv6 Sockets options introduced by RFC 3542
• the constant __APPLE_USE_RFC_3542 must be defined before
• including <netinet/in.h>
• To use the old IPv6 Sockets options from RFC 2292
• the constant __APPLE_USE_RFC_2292 must be defined before
• including <netinet/in.h>
• Note that eventually RFC 3542 is going to be the
• default and RFC 2292 will be obsolete. */

My conclusion from reading this: the name might suggest that this is an internal macro, but should be safe to use.