diff --git a/dmenu.c b/dmenu.c
index e0c2f80..72f8207 100644
--- a/dmenu.c
+++ b/dmenu.c
@@ -1,5 +1,6 @@
 /* See LICENSE file for copyright and license details. */
 #include <ctype.h>
+#include <errno.h>
 #include <locale.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -15,6 +16,13 @@
 #endif
 #include <X11/Xft/Xft.h>
 
+/* portability */
+#ifdef __OpenBSD__
+#include <unistd.h>
+#else
+int pledge(const char *promises, const char *paths[]) { return 0; }
+#endif
+
 #include "drw.h"
 #include "util.h"
 
@@ -491,11 +499,21 @@ readstdin(void)
 	lines = MIN(lines, i);
 }
 
+void
+xpledge(const char *promises, const char *paths[])
+{
+	if (pledge(promises, paths) < 0) {
+		die("dmenu: pledge: %s (%s)\n", strerror(errno), promises);
+	}
+}
+
 static void
 run(void)
 {
 	XEvent ev;
 
+	xpledge("stdio", NULL);
+
 	while (!XNextEvent(dpy, &ev)) {
 		if (XFilterEvent(&ev, win))
 			continue;
@@ -654,6 +672,8 @@ main(int argc, char *argv[])
 		else
 			usage();
 
+	xpledge("stdio rpath dns unix", NULL);
+
 	if (!setlocale(LC_CTYPE, "") || !XSupportsLocale())
 		fputs("warning: no locale support\n", stderr);
 	if (!(dpy = XOpenDisplay(NULL)))
@@ -668,6 +688,8 @@ main(int argc, char *argv[])
 		die("no fonts could be loaded.\n");
 	drw_setscheme(drw, &scheme[SchemeNorm]);
 
+	xpledge("stdio rpath", NULL);
+
 	if (fast) {
 		grabkeyboard();
 		readstdin();