--- lib/readln.c
+++ lib/readln.c
@@ -9,6 +9,7 @@
  * Get a single line from an fd.
  */
 
+#include <string.h>
 #include <stdlib.h>
 #include <unistd.h>
 #include <sys/types.h>

--- lib/cmdopen.c
+++ lib/cmdopen.c
@@ -6,6 +6,7 @@
  */
 
 #include <unistd.h>
+#include <stdlib.h>
 #include <fcntl.h>
 #include <sys/wait.h>