Although I don't read this list daily, I do keep an eye on it
and Helen gently pointed out to me that someone (Peter Lee)
was having an issue with the Firebird Port for MacOSX.
As the port maintainer (along with Solaris and HPUX) let
me explain how it works in regards to libfbclient and libfbembed...

Fulvio is nearly right - but he is referring to the Classic build not
SuperServer :-)

Firebird on MacOSX is delivered as a framework,

For more information on a frameowrk:
http://developer.apple.com/documentation/MacOSX/Conceptual/BPFrameworks/Concepts/WhatAreFrameworks.html#//apple_ref/doc/uid/20002303
-BBCEIJFI

In a nutshell - "A framework is a hierarchical directory that encapsulates
shared resources, such as a dynamic shared library, nib files, image files,
localized strings, header files, and reference documentation in a single package.
Multiple applications can use all of these resources simultaneously. The system l
oads them into memory as needed and shares the one copy of the resource among
all applications whenever possible."

This is the "best" way to deliver an application on MacOSX.

However to do this the main dylibs (shared libraries) that run Firebird become
part of the framework itself.

The main dylib that drives Classic is libfbembed, for SuperServer its libfbclient.

With Classic we ship both libfbembed and libfbclient, libfbclient as a separate
dylib can ve found in the libraries directory.

for SuperServer we ship libfbclient

However libfbembed (Classic) and libfbclient (SuperServer) are not directly obvious
as shared libraries, i.e. if you look for them by that name with a dylib extension
you are not going to find them. If you look at postfix.darwin in the firebird
source builds/posix (this is the code that sets up the framework)
you will find that they become Firebird.framework/Firebird
which is a link to Firebird.framework/Versions/Current/Firebird.

Hope this helps.

Paul