Link libcaca with -lgnugetopt if necessary.

caca/Makefile.am

@@ -55,7 +55,7 @@ libcaca_la_DEPENDENCIES = \
 	$(NULL)
 libcaca_la_CPPFLAGS = $(AM_CPPFLAGS) @CACA_CFLAGS@ -D__LIBCACA__
 libcaca_la_LDFLAGS = -no-undefined -version-number @LT_VERSION@
-libcaca_la_LIBADD = @CACA_LIBS@ $(ZLIB_LIBS)
+libcaca_la_LIBADD = @CACA_LIBS@ $(ZLIB_LIBS) $(GETOPT_LIBS)
 
 codec_source = \
 	codec/import.c \

src/Makefile.am

@@ -32,7 +32,7 @@ cacaserver_LDADD = ../caca/libcaca.la
 img2txt_SOURCES = img2txt.c $(GETOPT) common-image.c common-image.h
 img2txt_LDADD = ../caca/libcaca.la
 img2txt_CFLAGS = $(IMLIB2_CFLAGS)
-img2txt_LDFLAGS = $(IMLIB2_LIBS) $(GETOPT_LIBS)
+img2txt_LDFLAGS = $(IMLIB2_LIBS)
 
 if USE_NETWORK
 fcntl_programs = cacaserver