illumos gate

In system headers (/usr/include/netdb.h), we have

    int getnameinfo(const struct sockaddr *_RESTRICT_KYWD, socklen_t,
        char *_RESTRICT_KYWD, socklen_t, char *_RESTRICT_KYWD, socklen_t, int);

    int getnameinfo(const struct sockaddr *sa, socklen_t salen,
        char *host, size_t hostlen, char *serv, size_t servlen, int flags);

Notably, socklen_t is not size_t for the third arg so with pedantic enough builds of code written in accordance with the docs, I get

    error: implicit conversion loses integer precision: 'size_t' (aka 'unsigned long')
        to 'socklen_t' (aka 'unsigned int') [-Werror,-Wshorten-64-to-32]

Upon further discussion on IRC, this seems to be a manpage problem (looks a lot like one in FreeBSD) while header actually conforms to POSIX: https://pubs.opengroup.org/onlinepubs/009604599/functions/getnameinfo.html

• Solaris docs are correct: https://docs.oracle.com/cd/E88353_01/html/E37843/getnameinfo-3c.html
• (Debian) Linux manpage and header are correct: it has socklen_t in all 3 spots
• FreeBSD 12 is "consistently" different:
  freebsd manpage indeed says:
  

      int getnameinfo(const struct sockaddr *sa, socklen_t salen,
          char *host, size_t hostlen, char *serv, size_t servlen, int flags);
  

  
  but their netdb.h also says:
  

      int getnameinfo(const struct sockaddr *, socklen_t,
          char *, size_t, char *, size_t, int);
  

Thanks to AndyF for the context research and links.