correctly test KSRC for sanity

git-svn-id: http://svn.digium.com/svn/zaptel/trunk@760 5390a7c7-147a-4af0-8ec9-7488f05a26cb

1 files changed, 2 insertions, 1 deletions

diff --git a/Makefile b/Makefile
index 215f64c..3c04ca2 100755
--- a/Makefile
+++ b/Makefile
@@ -121,7 +121,8 @@ all: $(BUILDVER) $(LIBTONEZONE_SO) manpages
 linux24: $(MODULESO) $(BINS)
 
 linux26: prereq $(BINS)
-	@if ! [ -d $(KSRC) ]; then echo "You do not appear to have the sources for the $(KVERS) kernel installed."; exit 1 ; fi
+	@echo $(KSRC)
+	@if [ -z "$(KSRC)" -o ! -d $(KSRC) ]; then echo "You do not appear to have the sources for the $(KVERS) kernel installed."; exit 1 ; fi
 	$(MAKE) -C $(KSRC) SUBDIRS=$(PWD) modules
 
 obj-m := $(MODULESO)