> If no extension is supplied, and your system supports it, the original file is kept open without a name while the output is redirected to a new file with the original filename. When perl exits, cleanly or not, the original file is unlinked.
Which system are you using? With macOS and Linux, I get no automatic .bak extension when not providing a backup suffix, i.e. it behaves like you want under these systems.
Update: Apparently, anonymous files are not supported by Windows: http://stackoverflow.com/a/30539016 which would explain the behaviour you describe.
says:
> If no extension is supplied, and your system supports it, the original file is kept open without a name while the output is redirected to a new file with the original filename. When perl exits, cleanly or not, the original file is unlinked.
Which system are you using? With macOS and Linux, I get no automatic .bak extension when not providing a backup suffix, i.e. it behaves like you want under these systems.
Update: Apparently, anonymous files are not supported by Windows: http://stackoverflow.com/a/30539016 which would explain the behaviour you describe.