diff --git a/src/console_internal.h b/src/console_internal.h
--- a/src/console_internal.h
+++ b/src/console_internal.h
@@ -69,7 +69,7 @@ extern IConsoleAlias *_iconsole_aliases;
 void IConsoleClearBuffer();
 
 /* Commands */
-void IConsoleCmdRegister(const char *name, IConsoleCmdProc *proc, IConsoleHook *hook = NULL);
+void IConsoleCmdRegister(const char *name, IConsoleCmdProc *proc, IConsoleHook *hook = nullptr);
 void IConsoleAliasRegister(const char *name, const char *cmd);
 IConsoleCmd *IConsoleCmdGet(const char *name);
 IConsoleAlias *IConsoleAliasGet(const char *name);