diff --git a/src/grib2.h.in b/src/grib2.h.in
index 42bb2de7..fd24b607 100644
--- a/src/grib2.h.in
+++ b/src/grib2.h.in
@@ -21,7 +21,6 @@
 #include <stdint.h>
 #include <string.h>
 #include <sys/types.h>
-#include <unistd.h>
 
 #define G2C_VERSION "@pVersion@" /**< Current version of NCEPLIBS-g2c library. */