Perl automatically tries cmd /c $command is executing $command fails (or something like that), so `dir` actually does work on Windows.

I consider that a bug since it harms error reporting.

>perl -e"print `dir /b`"
bar
foo

Windows:
>perl -le"`nonexistant`; print $?; print $! if $?==-1"
'nonexistant' is not recognized as an internal or external command,
operable program or batch file.
256

unix:
$ perl -le'`nonexistant`; print $?; print $! if $?==-1'
-1
No such file or directory
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