1 files changed, 32 insertions, 0 deletions
diff --git a/linux-user/include/special-errno.h b/linux-user/include/special-errno.h
new file mode 100644
index 0000000000..4120455baa
--- /dev/null
+++ b/linux-user/include/special-errno.h
@@ -0,0 +1,32 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * QEMU internal errno values for implementing user-only POSIX.
+ *
+ *  Copyright (c) 2003 Fabrice Bellard
+ *  Copyright (c) 2021 Linaro, Ltd.
+ */
+
+#ifndef SPECIAL_ERRNO_H
+#define SPECIAL_ERRNO_H
+
+/*
+ * All of these are QEMU internal, not visible to the guest.
+ * They should be chosen so as to not overlap with any host
+ * or guest errno.
+ */
+
+/*
+ * This is returned when a system call should be restarted, to tell the
+ * main loop that it should wind the guest PC backwards so it will
+ * re-execute the syscall after handling any pending signals.
+ */
+#define QEMU_ERESTARTSYS  512
+
+/*
+ * This is returned after a successful sigreturn syscall, to indicate
+ * that it has correctly set the guest registers and so the main loop
+ * should not touch them.
+ */
+#define QEMU_ESIGRETURN   513
+
+#endif /* SPECIAL_ERRNO_H */