> > Have you checked config.log? Maybe the order of the checks is important. > > I've been using the following for ages, and it continues to work on > > Solaris 9: > > > > AC_CHECK_FUNCS(gethostbyname,,[AC_CHECK_LIB(nsl,gethostbyname,,[AC_CHECK_LIB(socket,gethostbyname)])]) > > AC_CHECK_FUNCS(setsockopt,,[AC_CHECK_LIB(socket,setsockopt)]) > > The checks appear to be working, I checked the logs. -lsocket and -lnsl > ARE in LIBS, but I need to add @LIBS@ to LDFLAGS in order to get this to > link. I've never had to do that before... It looks to me like the problem is in the Makefile then. You may want to post more details, and version numbers of the tools involved, either here or on the automake list, whichever is more appropriate.