> if not exist mydir/nul md mydir
> Doesn't work on XP (I think?), but that's the typical "DOS" way.

This kept bothering me for some reason, so I checked now.

It appears to work just fine on MSW NT command lines, executing the  
command after "if not exist dir\nul" if and only if that directory doesn't  
exist. In NTVDM, it does work as well (only?) using the COMMAND.COM  
supplied with NT; however, with other COMMAND.COMs (including FreeCOM) it  
indeed doesn't work: device names (such as NUL and CON) apparently aren't  

So while checking for a directory's existence with this method might work  
in non-DOS NT batch scripts, it can't be relied upon because the NTVDM's  
DOS interfaces appear not to find device names.


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