What does errno 103 (ENOPOLICY) in Mac mean?

ENOPOLICY

ENOPOLICY: Darwin cannot resolve the requested policy

ENOPOLICY is a Darwin-specific errno used when an API refers to a policy name or identifier that the active policy framework does not know. The failure is a policy-registration lookup, not resource exhaustion and not a portable POSIX policy error.

Evidence that separates the cause

Record the exact policy identifier, the API or ioctl that accepted it, the component expected to register the policy, the process entitlement/sandbox context, and the OS build. If registration is dynamic, also capture whether the provider loaded successfully in the current boot or session.

Focused correction

Confirm the policy is supported on that macOS release and registered before use. If the policy belongs to a removed or private provider, stop requesting it rather than substituting an unrelated identifier. Repeat the original call with the same caller and policy after registration is known to exist.

Technical references

• Apple XNU errno.h.
• Darwin system-call error conventions.