What
Claude Code saves some files in two steps. It first writes a temporary copy, then swaps it in place of the original. Two parts of that process are different now:
- Busy files on NFS: if the swap fails, Claude Code retries it once. NFS is a way of sharing folders over a network.
- Fallback writing: when Claude Code falls back to writing straight into the existing file, it now checks whether another program has replaced that file in the meantime. If it has, Claude Code leaves the file as it is, and the error message says another writer replaced it.
Before, the fallback deleted the target file, and the error always said the file had been truncated, meaning emptied.
Why
Fewer saves should be lost or overwritten when you work in a network folder or when another program writes to the same file at the same time.