Constant RAY_IPC_ERR_REFUSED 

pub const RAY_IPC_ERR_REFUSED: i64 = -1;

ray_ipc_connect failure codes.

The public header declares the function with no contract at all (include/rayforce.h); this mirrors the comment on the private src/core/ipc.h declaration and, for RAY_IPC_ERR_OS, the connect_fail_code() classifier in src/core/ipc.c that the header’s comment predates. Hand-maintained against a core bump, like Q_ERR_*.

RAY_IPC_ERR_REFUSED is the documented name for -1, but the core also returns it for a missing poll, a credential buffer overflow and a failed poll registration — treat it as the catch-all it is.