---
title: OS_SIGNPOST_ID_INVALID
framework: os
role: symbol
role_heading: Macro
path: os/os_signpost_id_invalid
---

# OS_SIGNPOST_ID_INVALID

A signpost identifier that indicates an error.

## Declaration

```occ
#define OS_SIGNPOST_ID_INVALID
```

## See Also

### Using Built-in Signpost Identifiers

- [OS_SIGNPOST_ID_EXCLUSIVE](os/os_signpost_id_exclusive.md)
- [OS_SIGNPOST_ID_NULL](os/os_signpost_id_null.md)