[BUG] Claude Code 2.1.30/2.1.31 silently exits on startup with code 0 on Linux 4.18.0

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Claude Code versions 2.1.30 and 2.1.31 silently exit immediately after startup with exit code 0. Version 2.1.19 works correctly. No error message is displayed.

Environment

• OS: Linux 4.18.0 (RHEL/CentOS)
• Node: v18.20.8
• Install method: Native installer
• Working version: 2.1.19
• Broken versions: 2.1.30, 2.1.31

Behavior

The process completes its full startup sequence, renders the welcome screen and REPL prompt, then silently exits with code 0 within ~1 second.

--version and --help work fine. Only interactive mode is affected.

Debug logs

Debug logs (~/.claude/debug/) confirm startup completes through [REPL:mount] REPL mounted, disabled=false, UI renders, and then the process exits with no error or crash logged.

Tested

• Different terminal sizes (18 rows to 40+ rows)
• Different TERM values (TERM=xterm-256color)
• Explicit stdin (< /dev/tty)
• Minimal environment (env -i HOME=$HOME PATH=$PATH TERM=$TERM)
• autoUpdates: false in .claude.json

All produce the same result.

Workaround

Pinned to 2.1.19 by setting the immutable flag on the versions directory to prevent the auto-updater from re-downloading broken versions:
chattr +i /root/.local/share/claude/versions/

Note: autoUpdates: false in .claude.json did not prevent the auto-updater from running.

What Should Happen?

Claude should not automatically exit on startup.

Error Messages/Logs

Steps to Reproduce

Simply start claude with the command : "claude"

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

2.1.19

Claude Code Version

2.1.31

Platform

Anthropic API

Operating System

Other Linux

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_