diff --git a/unix/modos.c b/unix/modos.c
index abc96e638df9462be7b0b0ac247004adf3871b01..9293d59d0fe3f5f03734039c1fb4c48ae2ca9b9c 100644
--- a/unix/modos.c
+++ b/unix/modos.c
@@ -201,8 +201,19 @@ STATIC mp_obj_t mod_os_ilistdir(mp_uint_t n_args, const mp_obj_t *args) {
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mod_os_ilistdir_obj, 0, 1, mod_os_ilistdir);
 
+STATIC mp_obj_t mod_os_errno(mp_uint_t n_args, const mp_obj_t *args) {
+    if (n_args == 0) {
+        return MP_OBJ_NEW_SMALL_INT(errno);
+    }
+
+    errno = mp_obj_get_int(args[0]);
+    return mp_const_none;
+}
+STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mod_os_errno_obj, 0, 1, mod_os_errno);
+
 STATIC const mp_rom_map_elem_t mp_module_os_globals_table[] = {
     { MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_uos) },
+    { MP_ROM_QSTR(MP_QSTR_errno), MP_ROM_PTR(&mod_os_errno_obj) },
     { MP_ROM_QSTR(MP_QSTR_stat), MP_ROM_PTR(&mod_os_stat_obj) },
     #if MICROPY_PY_OS_STATVFS
     { MP_ROM_QSTR(MP_QSTR_statvfs), MP_ROM_PTR(&mod_os_statvfs_obj) },
diff --git a/unix/qstrdefsport.h b/unix/qstrdefsport.h
index 9965c030c4c5acd5da5996617feca63ef13408e9..d761c0f54126342aa5c1f430c64c10151b6fbe80 100644
--- a/unix/qstrdefsport.h
+++ b/unix/qstrdefsport.h
@@ -44,6 +44,7 @@ Q(unlink)
 Q(getenv)
 Q(mkdir)
 Q(ilistdir)
+Q(errno)
 
 Q(uselect)
 Q(poll)