--- a/zuluCrypt-cli/bin/security.h
+++ b/zuluCrypt-cli/bin/security.h
@@ -35,7 +35,7 @@ extern "C" {
  * set the function to be called when an attempt to evelate or downgrade privileges fail
  * zuluCryptSecurityPrivilegeElevationError global variable is defined in security.c
  */
-void ( *zuluCryptSecurityPrivilegeElevationError )( const char * ) ;
+extern void ( *zuluCryptSecurityPrivilegeElevationError )( const char * ) ;
 
 void zuluCryptSecuritySetPrivilegeElevationErrorFunction( void ( * ) ( const char * ) ) ;