[Windows 11] Shell snapshot path error with Cygdrive paths

Bug Report: Shell snapshot path error on Windows 11

Description

Claude Code consistently throws bash path errors on Windows 11 when executing any bash command, although commands still execute successfully.

Error Messages

/usr/bin/bash: line 1: /cygdrive/c/Users/[USERNAME]/.claude/shell-snapshots/snapshot-bash-*.sh: No such file or directory
/usr/bin/bash: line 1: /cygdrive/c/Users/[USERNAME]/AppData/Local/Temp/claude-[ID]-cwd: No such file or directory

Environment

• OS: Windows 11
• Platform: win32
• Claude Code Model: claude-sonnet-4-5-20250929
• Node Version: v24.13.0
• Shell: /usr/bin/bash (Cygwin-style path detected)

Steps to Reproduce

1. Install Claude Code on Windows 11
2. Run any bash command (e.g., node -v)
3. Observe the error messages in stderr

Expected Behavior

Commands should execute without path-related errors in stderr.

Actual Behavior

Every bash command execution produces:

• "No such file or directory" errors for shell snapshot files
• "No such file or directory" errors for temporary working directory files
• Commands still execute successfully, but stderr is polluted with errors

Impact

• Severity: Medium (commands work but UX is degraded)
• User Experience: Confusing error messages appear on every command
• Windows 11 Users: Affects Windows environment specifically

Root Cause Analysis

The issue appears to be related to:

1. Path format mismatch: Claude Code is using Cygwin-style paths (/cygdrive/c/...) on Windows
2. Temporary file creation/access failing in the shell snapshot mechanism
3. Possible issue with shell environment detection on Windows

Suggested Fix

• Improve Windows path handling in the shell snapshot mechanism
• Detect Windows environment and use appropriate path formats
• Ensure temporary files are created with correct Windows-compatible paths

Additional Context

This affects the user experience for Windows 11 users and should be prioritized to improve cross-platform compatibility.

Reproduction Rate

100% - occurs on every bash command execution

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Note: This issue was reported to improve Windows 11 support and user experience in Claude Code.