diff --git a/.gitignore b/.gitignore
index 794e35b..2dfbbe1 100644
diff --git a/src/tools/make_ctags b/src/tools/make_ctags
index 1609c07..1e71692 100755
--- a/src/tools/make_ctags
+++ b/src/tools/make_ctags
@@ -2,6 +2,9 @@
 
 # src/tools/make_ctags
 
+command -v ctags >/dev/null || \
+	{ echo "'ctags' utility is not found" 1>&2; exit 1;}
+
 trap "rm -f /tmp/$$" 0 1 2 3 15
 rm -f ./tags
 
diff --git a/src/tools/make_etags b/src/tools/make_etags
index 3ce96bc..6dc6710 100755
--- a/src/tools/make_etags
+++ b/src/tools/make_etags
@@ -2,6 +2,9 @@
 
 # src/tools/make_etags
 
+command -v etags >/dev/null || \
+	{ echo "'etags' utility is not found" 1>&2; exit 1;}
+
 rm -f ./TAGS
 
 find `pwd`/ -type f -name '*.[chyl]' -print |