--- a/libbb/gz_open.c
+++ b/libbb/gz_open.c
@@ -29,7 +29,12 @@
 #include <unistd.h>
 #include "libbb.h"
 
+#ifdef OPKG_USE_VFORK
+static const int gz_use_vfork = OPKG_USE_VFORK;
+#else
 static int gz_use_vfork;
+#endif
+
 
 FILE *
 gz_open(FILE *compressed_file, int *pid)
@@ -38,7 +43,9 @@ gz_open(FILE *compressed_file, int *pid)
 	off_t floc;
 	int cfile = -1;
 
+#ifndef OPKG_USE_VFORK
 	gz_use_vfork = (getenv("OPKG_USE_VFORK") != NULL);
+#endif
 
 	if (gz_use_vfork) {
 		/* Create a new file descriptor for the input stream