E1209 — Sandbox violation (forbidden syscall)

Property	Value
Code	`1209`
Slug	`E1209`
Category	`runtime` (Runtime)

What happened

Sandbox violation (forbidden syscall). This is the receipt’s what text, produced by the host-call result HostError::SandboxViolation.

Why it happened

The node rejected the operation with E1209 (category runtime, Runtime). The receipt’s why field carries the specific cause and context carries structured details, when the emitter attaches any.

How to fix

The actor attempted a syscall the PVM sandbox forbids (deterministic seccomp kill). Remove the disallowed operation (filesystem/network/subprocess/etc.) from the handler.

Receipt example

{
  "code": 1209,
  "slug": "E1209",
  "category": "runtime",
  "what": "sandbox violation (forbidden syscall)",
  "fix": "The actor attempted a syscall the PVM sandbox forbids (deterministic seccomp kill). Remove the disallowed operation (filesystem/network/subprocess/etc.) from the handler.",
  "docs_url": "https://docs.cowboy.inc/errors/E1209"
}

All Error Codes

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