[BUG] Read refuses any path containing a backslash: "its symlink resolution changed after permission was checked"

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?

On Linux, Read refuses every file whose path contains a backslash, even a plain regular file that is not a symlink:

Refusing to read /tmp/x/a\x2db.txt: its symlink resolution changed after permission was checked (its real path can no longer be determined). If a link in the working directory is being rewritten concurrently, stop that and retry.

Backslash is a valid filename character on Linux, and systemd escapes - in unit names as \x2d, so every mount or automount unit for a path with a dash looks like mnt-foo\x2dbar.mount. Write creates such a file fine, but after that the file can't be read, and since Edit and overwriting Write need a prior Read, it can't be edited either. The only way left is shell commands.

It looks like the path is normalized with \ treated as a separator somewhere between the permission check and the real-path check, so the two never match.

What Should Happen?

On POSIX platforms a backslash in a path is an ordinary character: Read, Edit and Write should work on mnt-foo\x2dbar.mount like on any other file.

Steps to Reproduce

1. mkdir -p /tmp/x && printf 'x\n' > '/tmp/x/a\x2db.txt'
2. Ask Claude to read /tmp/x/a\x2db.txt with the Read tool.
3. Read fails with the message above. ls -la shows a regular file, no symlinks anywhere in the path.

Claude Model

Not sure / Multiple models

Is this a regression?

I don't know

Claude Code Version

2.1.284 (Claude Code)

Platform

Anthropic API

Operating System

Ubuntu/Debian Linux

Terminal/Shell

Other