diff --git a/libs/libc/unistd/lib_pathconf.c b/libs/libc/unistd/lib_pathconf.c
index 69d750a62f5..fa9387fbc24 100644
--- a/libs/libc/unistd/lib_pathconf.c
+++ b/libs/libc/unistd/lib_pathconf.c
@@ -136,6 +136,9 @@ long fpathconf(int fildes, int name)
       case _PC_MAX_INPUT:
         return _POSIX_MAX_INPUT;
 
+      case _PC_PRIO_IO:
+        return -1;
+
       default:
 
         /* Assume valid but not implemented for the time being */