/fork leaves parent thread with active writer, preventing resume in another terminal
Open
Nobody has claimed this yet.
bug
CLI
session
- Dominant language
- Rust
- Stars
- 125k
- Forks
- 19.5k
- PR merge metrics
- PR metrics pending
Description
What version of Codex CLI is running?
codex-cli 0.147.0
What subscription do you have?
Pro
Which model were you using?
gpt-5.6-sol
What platform is your computer?
Linux 5.15.167.4-microsoft-standard-WSL2 x86_64 x86_64
What terminal emulator and version are you using (if applicable)?
WSL
Codex doctor report
{
"schemaVersion": 1,
"generatedAt": "1786518424s since unix epoch",
"overallStatus": "warning",
"codexVersion": "0.147.0",
"checks": {
"app_server.status": {
"id": "app_server.status",
"category": "app-server",
"status": "ok",
"summary": "background server is not running",
"details": {
"control socket": "/home/[REDACTED_USER]/.codex/app-server-control/app-server-control.sock",
"daemon state dir": "/home/[REDACTED_USER]/.codex/app-server-daemon",
"mode": "ephemeral",
"pid file": "/home/[REDACTED_USER]/.codex/app-server-daemon/app-server.pid (missing)",
"settings": "/home/[REDACTED_USER]/.codex/app-server-daemon/settings.json (missing)",
"status": "not running",
"update-loop pid file": "/home/[REDACTED_USER]/.codex/app-server-daemon/app-server-updater.pid (missing)"
},
"remediation": null,
"durationMs": 0
},
"auth.credentials": {
"id": "auth.credentials",
"category": "auth",
"status": "ok",
"summary": "auth is configured",
"details": {
"auth env vars present": "OPENAI_API_KEY",
"auth file": "/home/[REDACTED_USER]/.codex/auth.json",
"auth storage mode": "File",
"stored API key": "false",
"stored ChatGPT tokens": "true",
"stored agent identity": "[REDACTED: identity metadata]",
"stored auth mode": "chatgpt"
},
"remediation": null,
"durationMs": 0
},
"config.load": {
"id": "config.load",
"category": "config",
"status": "ok",
"summary": "config loaded",
"details": {
"CODEX_HOME": "/home/[REDACTED_USER]/.codex",
"config.toml": "/home/[REDACTED_USER]/.codex/config.toml",
"config.toml parse": "ok",
"cwd": "/home/[REDACTED_USER]/code/ai-content-pipeline",
"enabled feature flags": "shell_tool, view_image, unified_exec, shell_snapshot, code_mode_host, terminal_resize_reflow, sqlite, memories, hooks, enable_request_compression, network_proxy, multi_agent, apps, tool_search_always_defer_mcp_tools, tool_suggest, plugins, in_app_browser, in_app_updates, browser_use, browser_use_full_cdp_access, browser_use_external, computer_use, remote_plugin, plugin_sharing, image_generation, resize_all_images, item_ids, skill_mcp_dependency_install, skill_search, mentions_v2, steer, guardian_approval, goals, collaboration_modes, tool_call_mcp_elicitation, auth_elicitation, personality, fast_mode, tui_app_server, remote_compaction_v2, workspace_dependencies",
"feature flag overrides": "memories=true, network_proxy=true",
"feature flags enabled": "41",
"log dir": "/home/[REDACTED_USER]/.codex/log",
"mcp servers": "[REDACTED: MCP server names]",
"model": "gpt-5.6-sol",
"model provider": "openai",
"sqlite home": "/home/[REDACTED_USER]/.codex"
},
"remediation": null,
"durationMs": 0
},
"git.environment": {
"id": "git.environment",
"category": "git",
"status": "ok",
"summary": "git version 2.43.0",
"details": {
".git entry": "[REDACTED: repository metadata]",
"PATH git #1": "/usr/bin/git",
"PATH git #2": "/bin/git",
"PATH git entries": "2",
"git branch": "[REDACTED: branch name]",
"git build options": "git version 2.43.0; cpu: x86_64; no commit associated with this build; sizeof-long: 8; sizeof-size_t: 8; shell-path: /bin/sh",
"git exec path": "/usr/lib/git-core",
"git version": "git version 2.43.0",
"repo detected": "true",
"repo root": "[REDACTED: repository path]",
"selected git": "/usr/bin/git"
},
"remediation": null,
"durationMs": 79
},
"installation": {
"id": "installation",
"category": "install",
"status": "ok",
"summary": "installation looks consistent",
"details": {
"PATH codex #1": "/home/[REDACTED_USER]/.local/bin/codex",
"PATH codex #2": "/home/[REDACTED_USER]/.local/bin/codex",
"PATH codex #3": "/home/[REDACTED_USER]/.local/bin/codex",
"PATH codex #4": "/home/[REDACTED_USER]/.local/bin/codex",
"PATH codex #5": "/home/[REDACTED_USER]/.local/bin/codex",
"PATH codex #6": "/home/[REDACTED_USER]/.local/bin/codex",
"PATH codex #7": "/mnt/c/nvm4w/nodejs/codex",
"PATH codex #8": "/mnt/c/nvm4w/nodejs/codex",
"PATH codex entries": "8",
"current executable": "/home/[REDACTED_USER]/.codex/packages/standalone/releases/0.147.0-x86_64-unknown-linux-musl/bin/codex",
"install context": "standalone (unix, package /home/[REDACTED_USER]/.codex/packages/standalone/releases/0.147.0-x86_64-unknown-linux-musl, bin /home/[REDACTED_USER]/.codex/packages/standalone/releases/0.147.0-x86_64-unknown-linux-musl/bin, resources /home/[REDACTED_USER]/.codex/packages/standalone/releases/0.147.0-x86_64-unknown-linux-musl/codex-resources, path /home/[REDACTED_USER]/.codex/packages/standalone/releases/0.147.0-x86_64-unknown-linux-musl/codex-path)",
"managed by bun": "false",
"managed by npm": "false",
"managed by pnpm": "false",
"managed package root": "not set"
},
"remediation": null,
"durationMs": 23
},
"mcp.config": {
"id": "mcp.config",
"category": "mcp",
"status": "ok",
"summary": "MCP configuration is locally consistent",
"details": {
"configured servers": "[REDACTED: MCP server names]",
"disabled servers": "[REDACTED: MCP server names]",
"stdio servers": "[REDACTED: MCP server names]",
"streamable_http servers": "[REDACTED: MCP server names]"
},
"remediation": null,
"durationMs": 3481
},
"network.env": {
"id": "network.env",
"category": "network",
"status": "ok",
"summary": "network-related environment looks readable",
"details": {
"proxy env vars": "[REDACTED: proxy configuration]"
},
"remediation": null,
"durationMs": 0
},
"network.provider_reachability": {
"id": "network.provider_reachability",
"category": "reachability",
"status": "ok",
"summary": "active provider endpoints are reachable over HTTP",
"details": {
"openai API base URL": "https://api.openai.com/v1 reachable (HTTP 404)",
"openai API route probe": "https://api.openai.com/v1/<redacted> route exists (HTTP 401)",
"reachability mode": "API key auth"
},
"remediation": null,
"durationMs": 682
},
"network.websocket_reachability": {
"id": "network.websocket_reachability",
"category": "websocket",
"status": "ok",
"summary": "Responses WebSocket handshake succeeded",
"details": {
"DNS": "[REDACTED: DNS result]",
"auth mode": "chatgpt",
"connect timeout": "15000 ms",
"endpoint": "wss://chatgpt.com/backend-api/<redacted>",
"handshake result": "HTTP 101 Switching Protocols",
"model provider": "openai",
"models etag present": "true",
"provider name": "OpenAI",
"proxy env vars": "[REDACTED: proxy configuration]",
"reasoning header": "false",
"server model present": "false",
"supports websockets": "true",
"wire API": "responses"
},
"remediation": null,
"durationMs": 1620
},
"runtime.provenance": {
"id": "runtime.provenance",
"category": "runtime",
"status": "ok",
"summary": "running standalone on linux-x86_64",
"details": {
"commit": "unknown",
"current executable": "/home/[REDACTED_USER]/.codex/packages/standalone/releases/0.147.0-x86_64-unknown-linux-musl/bin/codex",
"install method": "standalone (unix, package /home/[REDACTED_USER]/.codex/packages/standalone/releases/0.147.0-x86_64-unknown-linux-musl, bin /home/[REDACTED_USER]/.codex/packages/standalone/releases/0.147.0-x86_64-unknown-linux-musl/bin, resources /home/[REDACTED_USER]/.codex/packages/standalone/releases/0.147.0-x86_64-unknown-linux-musl/codex-resources, path /home/[REDACTED_USER]/.codex/packages/standalone/releases/0.147.0-x86_64-unknown-linux-musl/codex-path)",
"platform": "linux-x86_64",
"version": "0.147.0"
},
"remediation": null,
"durationMs": 0
},
"runtime.search": {
"id": "runtime.search",
"category": "search",
"status": "ok",
"summary": "search is OK (bundled)",
"details": {
"search command": "/home/[REDACTED_USER]/.codex/packages/standalone/releases/0.147.0-x86_64-unknown-linux-musl/codex-path/rg",
"search command readiness": "file exists",
"search provider": "bundled"
},
"remediation": null,
"durationMs": 0
},
"sandbox.helpers": {
"id": "sandbox.helpers",
"category": "sandbox",
"status": "ok",
"summary": "sandbox configuration is readable",
"details": {
"approval policy": "OnRequest",
"codex-linux-sandbox helper": "/home/[REDACTED_USER]/.codex/tmp/[REDACTED]",
"execve wrapper helper": "/home/[REDACTED_USER]/.codex/tmp/[REDACTED]",
"filesystem sandbox": "restricted",
"network sandbox": "restricted"
},
"remediation": null,
"durationMs": 0
},
"state.paths": {
"id": "state.paths",
"category": "state",
"status": "ok",
"summary": "state paths and databases are inspectable",
"details": {
"CODEX_HOME": "/home/[REDACTED_USER]/.codex (dir)",
"active rollout files": "1404 files, 1578995851 total bytes, 1124640 average bytes",
"archived rollout files": "0 files, 0 total bytes, 0 average bytes",
"goals DB": "/home/[REDACTED_USER]/.codex/goals_1.sqlite (file)",
"goals DB integrity": "ok",
"log DB": "/home/[REDACTED_USER]/.codex/logs_2.sqlite (file)",
"log DB integrity": "ok",
"log dir": "/home/[REDACTED_USER]/.codex/log (dir)",
"memories DB": "/home/[REDACTED_USER]/.codex/memories_1.sqlite (file)",
"memories DB integrity": "ok",
"queue DB": "/home/[REDACTED_USER]/.codex/queue_1.sqlite (file)",
"queue DB integrity": "ok",
"sqlite home": "/home/[REDACTED_USER]/.codex (dir)",
"standalone release cache": "3 entries in /home/[REDACTED_USER]/.codex/packages/standalone/releases",
"state DB": "/home/[REDACTED_USER]/.codex/state_5.sqlite (file)",
"state DB integrity": "ok",
"thread history DB": "/home/[REDACTED_USER]/.codex/thread_history_1.sqlite (file)",
"thread history DB integrity": "ok"
},
"remediation": null,
"durationMs": 4889
},
"state.rollout_db_parity": {
"id": "state.rollout_db_parity",
"category": "threads",
"status": "warning",
"summary": "rollout files and state DB thread inventory differ",
"details": {
"default model provider": "openai",
"rollout DB active files": "1400",
"rollout DB active rows": "1395",
"rollout DB archive mismatches": "0",
"rollout DB archived files": "0",
"rollout DB archived rows": "0",
"rollout DB duplicate DB paths": "0",
"rollout DB duplicate rollout thread ids": "0",
"rollout DB malformed file names": "0",
"rollout DB missing active rows": "5",
"rollout DB missing active sample": [
"[REDACTED: rollout path and identifier]"
],
"rollout DB missing archived rows": "0",
"rollout DB model providers": "openai=1395",
"rollout DB rows": "1395",
"rollout DB scan cap reached": "false",
"rollout DB scan error sample": [
"[REDACTED: rollout path and identifier]"
],
"rollout DB scan errors": "4",
"rollout DB sources": "cli=448, subagent:thread_spawn=407, vscode=340, subagent:review=188, exec=12",
"rollout DB stale rows": "0"
},
"issues": [
{
"severity": "warning",
"cause": "rollout files are missing from the state DB",
"measured": "5 active, 0 archived",
"expected": "every rollout file has a matching threads row",
"remedy": null,
"fields": []
},
{
"severity": "warning",
"cause": "rollout scan was incomplete or found bad files",
"measured": "4 scan errors, 0 malformed names, scan cap reached: false",
"expected": "rollout directories are fully scannable",
"remedy": "Check file permissions and unexpected files under CODEX_HOME sessions.",
"fields": []
}
],
"remediation": null,
"durationMs": 988
},
"system.environment": {
"id": "system.environment",
"category": "system",
"status": "ok",
"summary": "OS language C",
"details": {
"EDITOR": "not set",
"LANG": "C.UTF-8",
"VISUAL": "not set",
"os": "Ubuntu 24.4.0 (noble) [64-bit]",
"os language": "C",
"os type": "Ubuntu",
"os version": "24.4.0"
},
"remediation": null,
"durationMs": 4
},
"terminal.env": {
"id": "terminal.env",
"category": "terminal",
"status": "ok",
"summary": "terminal metadata was detected",
"details": {
"COLORTERM": "truecolor",
"DISPLAY": "[REDACTED: local display endpoint]",
"TERM_PROGRAM": "vscode",
"VSCODE_IPC_HOOK_CLI": "[REDACTED: local IPC path]",
"WAYLAND_DISPLAY": "[REDACTED: local display endpoint]",
"WSL_DISTRO_NAME": "present",
"WSL_INTEROP": "[REDACTED: local IPC path]",
"color output": "enabled",
"effective locale": "C.UTF-8",
"stderr is terminal": "true",
"stdin is terminal": "true",
"stdout is terminal": "true",
"terminal": "VS Code",
"terminal size": "306x37",
"terminal version": "1.132.1"
},
"remediation": null,
"durationMs": 0
},
"terminal.title": {
"id": "terminal.title",
"category": "title",
"status": "ok",
"summary": "terminal title default",
"details": {
"redacted": "[REDACTED: terminal project metadata]"
},
"remediation": null,
"durationMs": 0
},
"updates.status": {
"id": "updates.status",
"category": "updates",
"status": "ok",
"summary": "update configuration is locally consistent",
"details": {
"cached latest version": "0.147.0",
"check for update on startup": "true",
"last checked at": "2026-08-12T06:19:22.738664369Z",
"latest version": "0.147.0",
"latest version status": "current version is not older",
"update action": "standalone installer",
"version cache": "/home/[REDACTED_USER]/.codex/version.json"
},
"remediation": null,
"durationMs": 783
}
}
}
What issue are you seeing?
/fork leaves the parent session with an active writer, so the parent session cannot be resumed in another terminal.
I am using Codex CLI 0.147.0.
Steps to reproduce:
- Start working in a Codex CLI session.
- Run:
/fork
- Codex switches to a new forked session.
- Run:
/status
The result confirms that the current TUI is attached to the new forked session:
Session: 019ff4b6-6708-7830-8f43-11ce2495c89f
Forked from: 019ff4a0-1d4d-79a3-a456-ab7187a79d02
After /fork, Codex also prints:
To continue this session, run codex resume 019ff4a0-1d4d-79a3-a456-ab7187a79d02
- In another terminal, run exactly that command:
codex resume 019ff4a0-1d4d-79a3-a456-ab7187a79d02
Instead of resuming the parent session, Codex fails with:
Error: Failed to resume session from /home/pavel/.codex/sessions/2026/08/12/rollout-2026-08-12T11-19-21-019ff4a0-1d4d-79a3-a456-ab7187a79d02.jsonl: thread/resume failed during TUI bootstrap: thread/resume failed: thread 019ff4a0-1d4d-79a3-a456-ab7187a79d02 already has an active writer (code -32600)
What steps can reproduce the bug?
Uploaded thread: 019ff4b6-6708-7830-8f43-11ce2495c89f
What is the expected behavior?
No response
Additional information
No response
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Start by reproducing the /fork flow and then attempting to resume the fork in another terminal. Trace the thread and writer lifecycle involved in that flow; done means the parent thread no longer retains an active writer and the fork can be resumed elsewhere.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- rust
- Domain
- cli
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Active
- Clarity
- Mostly clear
- Newbie friendliness
- 48/100