custom basename(3) and dirname(3)

diff --git a/configure.in b/configure.in
index 05d03ca..7585ced 100644
--- a/configure.in
+++ b/configure.in
@@ -67,7 +67,7 @@
 
 dnl Checks for header files.
 AC_HEADER_STDC
-AC_CHECK_HEADERS(errno.h)
+AC_CHECK_HEADERS(sys/param.h)
 
 dnl Checks for typedefs, structures, and compiler characteristics.
 AC_C_BIGENDIAN