diff --git a/include/glibtop/xmalloc.h b/include/glibtop/xmalloc.h
index 4a67212d..ce9dac18 100644
--- a/include/glibtop/xmalloc.h
+++ b/include/glibtop/xmalloc.h
@@ -30,7 +30,7 @@ __BEGIN_DECLS
 #define glibtop_malloc(p1)	glibtop_malloc_r(glibtop_global_server, p1)
 #define glibtop_calloc(p1, p2)	glibtop_calloc_r(glibtop_global_server, p1, p2)
 #define glibtop_realloc(p1, p2)	glibtop_realloc_r(glibtop_global_server, p1, p2)
-#define glibtop_strdup(p2)	glibtop_strdup_r(glibtop_global_server, p1)
+#define glibtop_strdup(p1)	glibtop_strdup_r(glibtop_global_server, p1)
 #define glibtop_free(p1)	glibtop_free_r(glibtop_global_server, p1)
 
 extern void *glibtop_malloc_r	__P((glibtop *, size_t));