From Lazarus wiki

English (en) français (fr) Bahasa Indonesia (id)

Netdb is a simple library for DNS resolving under *nix. It forms the basis of FCL level DNS resolving which is truely platform independant.

After being broken for a while, after 1.9.8 some serious fixes were made, and now the IPV4 calls should be in at least usable form for FreeBSD/Linux/Darwin on x86 and powerpc.

The most common misconception about netdb is that the gethostbyname is a direct alternative for the libc call with the same name (which resolves a host). However the netdb call gethostbyname really only checks /etc/hosts, and netdb resolvename only checks the DNS servers listed in /etc/resolv.conf.

This has the following consequences:

  • it takes two calls to resolve a name (one to check hosts, one to check dns) (i.o.w. testdns and testhost code is both needed)
  • the LOOKUP (OpenBSD) command in resolv.conf is not processed.
  • Other forms of resolving than /etc/hosts and (like YP) are not supported.
  • Setting FPC_USE_LIBC doesn't have any consequences yet, the non-libc code will still be used.