[BUG] EPERM error when writing/editing files on SSHFS/FUSE-mounted filesystem

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 fails to write or edit files when the project is located on an SSHFS-mounted network drive. When attempting to edit an existing file, the operation fails with Write failed and an EPERM (Operation not permitted) error.

What Should Happen?

File is written successfully, same as when the project is on a local filesystem.

Error Messages/Logs

Observe Write failed / EPERM error

Steps to Reproduce

To Reproduce

Mount a remote filesystem via SSHFS
Open the mounted project in VS Code with Claude Code extension
Ask Claude Code to edit any file
Observe Write failed / EPERM error

Claude Model

Sonnet (default)

Is this a regression?

No, this never worked

Last Working Version

_No response_

Claude Code Version

2.1.259

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information

GitHub Copilot edits files on the same SSHFS mount without any issues, since it uses vscode.workspace.fs API which is filesystem-agnostic
The PowerShell workaround succeeds but causes VS Code to lose edit history/checkpoint for those changes, since the write happens outside of VS Code's awareness
Remote SSH extension works fine as an alternative mount method