+ifdef HAS_SHADOW
+CFLAGS += -DHAS_SHADOW
+#LIBS := -lshadow $(LIBS)
+endif
+
+# For "Pluggable Authentication Modules", see ftp.redhat.com:/pub/pam/.
+ifdef USE_PAM
+CFLAGS += -DUSE_PAM
+LIBS := -lpam -ldl $(LIBS)
+endif
+
+# Lock library binary for Linux is included in 'linux' subdirectory.
+ifdef LOCKLIB
+LIBS := -llock $(LIBS)
+CFLAGS += -DLOCKLIB=1
+endif
+
+ifdef PLUGIN
+CFLAGS += -DPLUGIN
+LDFLAGS += -Wl,-E
+LIBS += -ldl
+endif
+
+ifdef HAVE_INET6
+ PPPDSRCS += ipv6cp.c eui64.c
+ HEADERS += ipv6cp.h eui64.h
+ PPPDOBJS += ipv6cp.o eui64.o
+ CFLAGS += -DINET6=1
+endif
+
+
+INSTALL= install -o root
+
+install: pppd
+ mkdir -p $(BINDIR) $(MANDIR)
+ $(INSTALL) -s -c -m 4550 pppd $(BINDIR)/pppd
+ if ! chgrp pppusers $(BINDIR)/pppd 2>/dev/null; then \
+ chmod o+rx $(BINDIR)/pppd; fi
+ $(INSTALL) -c -m 444 pppd.8 $(MANDIR)/man8
+
+pppd: $(PPPDOBJS)
+ $(CC) $(CFLAGS) $(LDFLAGS) -o pppd $(PPPDOBJS) $(LIBS)