6 ms·

Even if Microsoft keeps this behavior, I'm surprised they don't modify it to check the filename extension. It's one thing to change a device like CON that peopl

Even if Microsoft keeps this behavior, I'm surprised they don't modify it to check the filename extension. It's one thing to change a device like CON that people might expect to exist, but it seems like not distinguishing CON and con.c is just asking for trouble.

dfox 9y ago
That behavior is intentional and is workaround for programs that does not let user change file extension on saving.
- ploxiln 9y ago
  The funny part is, that is not the purpose at all any more. It was probably only for a handful of years that this trick was needed to "trick" programs which thought they were saving a normal file and forcing the correct extension to actually use a printer or serial port. No one has used a printer or serial port by File -> Save As to "lpt.txt" in decades! Now it's just because some code hidden away under 10s of layers a millions of lines in some obscure line-of-business applications is accidentally dependent on this quirk and "it works now" and no one will ever fix it.
  - kevin_thibedeau 9y ago
    This isn't an issue for contemporary human facing UIs. Somewhere there is guaranteed to be a crusty POS system still in use that is sending receipt data to LPT.TXT or AUX.TXT.
    - flukus 9y ago
      They could remove it in a new version of windows, that crusty POS system is going to be doing a lot of testing before they upgrade the version of windows it's running on. Even more likely is that they'll never upgrade from whatever ancient version they're using so it won't affect anyone. I think they just keep it because it feeds into the backwards compatibility myth that MS has built up.
      - colejohnson66 9y ago
        Or they could just create a registry flag that enables the backwards compatible behavior. Then all default installs don't have the "bug", while those that need it can enable it.
        captainmuon 9y ago
        They could probably make the new behavior opt-in in the application manifest. Without a manifest, you'll see pre-XP common controls, and GetVersion will return an old version, so every modern application has it anyway.
        therein 9y ago
        They could even incorporate this into some sort of... Compatibility Mode.
        Arnavion 9y ago
        Batch scripts don't have application manifests (nor, to the sibling comment, a compat mode setting).
    - dfox 9y ago
      I would not be that surprised if even in this year's version of some niche CADs the most sane way to print the drawing in correct scale on DesignJet is to export the document as 'PRN.HPG' or something similar.
breadbox 9y ago
Possibly. On the other hand, you're talking about changing behavior that's been in place for 35 years. It's more than a little late to garner any benefit from changing it. And the risk that you'll actually break an existing program somewhere is certainly small but probably not zero.
jdboyd 9y ago
Or they could have at least removed the behavior when in 64bit mode.

dfox 9y ago

That behavior is intentional and is workaround for programs that does not let user change file extension on saving.

ploxiln 9y ago
The funny part is, that is not the purpose at all any more. It was probably only for a handful of years that this trick was needed to "trick" programs which thought they were saving a normal file and forcing the correct extension to actually use a printer or serial port. No one has used a printer or serial port by File -> Save As to "lpt.txt" in decades! Now it's just because some code hidden away under 10s of layers a millions of lines in some obscure line-of-business applications is accidentally dependent on this quirk and "it works now" and no one will ever fix it.
- kevin_thibedeau 9y ago
  This isn't an issue for contemporary human facing UIs. Somewhere there is guaranteed to be a crusty POS system still in use that is sending receipt data to LPT.TXT or AUX.TXT.
  - flukus 9y ago
    They could remove it in a new version of windows, that crusty POS system is going to be doing a lot of testing before they upgrade the version of windows it's running on. Even more likely is that they'll never upgrade from whatever ancient version they're using so it won't affect anyone. I think they just keep it because it feeds into the backwards compatibility myth that MS has built up.
    - colejohnson66 9y ago
      Or they could just create a registry flag that enables the backwards compatible behavior. Then all default installs don't have the "bug", while those that need it can enable it.
      - captainmuon 9y ago
        They could probably make the new behavior opt-in in the application manifest. Without a manifest, you'll see pre-XP common controls, and GetVersion will return an old version, so every modern application has it anyway.
        therein 9y ago
        They could even incorporate this into some sort of... Compatibility Mode.
        Arnavion 9y ago
        Batch scripts don't have application manifests (nor, to the sibling comment, a compat mode setting).
  - dfox 9y ago
    I would not be that surprised if even in this year's version of some niche CADs the most sane way to print the drawing in correct scale on DesignJet is to export the document as 'PRN.HPG' or something similar.

breadbox 9y ago

Possibly. On the other hand, you're talking about changing behavior that's been in place for 35 years. It's more than a little late to garner any benefit from changing it. And the risk that you'll actually break an existing program somewhere is certainly small but probably not zero.

jdboyd 9y ago

Or they could have at least removed the behavior when in 64bit mode.