diff --git a/include/linux/syscall.h b/include/linux/syscall.h
index 0af5fd70..8cc1a27a 100644
--- a/include/linux/syscall.h
+++ b/include/linux/syscall.h
@@ -1,6 +1,7 @@
 /* -*-comment-start: "//";comment-end:""-*-
  * GNU Mes --- Maxwell Equations of Software
  * Copyright © 2016,2017,2018,2019 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
+ * Copyright © 2021 W. J. van der Laan <laanwj@protonmail.com>
  *
  * This file is part of GNU Mes.
  *
@@ -26,6 +27,7 @@ long _sys_call1 (long sys_call, long one);
 long _sys_call2 (long sys_call, long one, long two);
 long _sys_call3 (long sys_call, long one, long two, long three);
 long _sys_call4 (long sys_call, long one, long two, long three, long four);
+long _sys_call5 (long sys_call, long one, long two, long three, long four, long five);
 long _sys_call6 (long sys_call, long one, long two, long three, long four, long five, long six);
 
 #endif //__MES_SYSCALL_H
diff --git a/lib/linux/riscv64-mes-gcc/syscall.c b/lib/linux/riscv64-mes-gcc/syscall.c
index b9006a49..45d679c9 100644
--- a/lib/linux/riscv64-mes-gcc/syscall.c
+++ b/lib/linux/riscv64-mes-gcc/syscall.c
@@ -93,6 +93,23 @@ __sys_call4 (long sys_call, long one, long two, long three, long four)
        );
   return __a0;
 }
+
+long
+__sys_call5 (long sys_call, long one, long two, long three, long four, long five)
+{
+  register long __a7 asm ("a7") = sys_call;
+  register long __a0 asm ("a0") = one;
+  register long __a1 asm ("a1") = two;
+  register long __a2 asm ("a2") = three;
+  register long __a3 asm ("a3") = four;
+  register long __a4 asm ("a4") = five;
+  asm volatile (
+       "ecall\n\t"
+       : "+r" (__a0)
+       : "r" (__a7), "r" (__a1), "r" (__a2), "r" (__a3), "r" (__a4)
+       );
+  return __a0;
+}
 // *INDENT-ON*
 
 long
@@ -164,3 +181,17 @@ _sys_call4 (long sys_call, long one, long two, long three, long four)
     errno = 0;
   return r;
 }
+
+long
+_sys_call5 (long sys_call, long one, long two, long three, long four, long five)
+{
+  long r = __sys_call5 (sys_call, one, two, three, four, five);
+  if (r < 0)
+    {
+      errno = -r;
+      r = -1;
+    }
+  else
+    errno = 0;
+  return r;
+}