$ cat _testdir_\_test_.bat
@echo %date% %time%

$ cat runit.pl


use IPC::Run;
IPC::Run::run(['_testdir_/_test_.bat']);
IPC::Run::run(['_testdir_\\_test_.bat']) ;

$ perl runit.pl
'_testdir_' is not recognized as an internal or external command,
operable program or batch file.
Thu 05/27/2010  6:47:20.93

$ _testdir_\_test_.bat
Thu 05/27/2010  6:47:27.87

$ _testdir_/_test_.bat
'_testdir_' is not recognized as an internal or external command,
operable program or batch file.
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Its invoking the shell

I would not expect that it does. From the perldocs:

       # Launch a sub process directly, no shell.  Can't do redirectio
+n
       # with this form, it's here to behave like system() with an
       # inverted result.
          $r = run "cat a b c" ;
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So this example explicitly says no shell.
-- 
Ronald Fischer <ynnor@mm.st>

system calls the shell when it's documented not to in Windows. According to the documentation, perl -e"system('dir')" and perl -e"system('foo.bat')" should fail, yet both work. This might be documented in perlport.

You're giving it a batch file, and only the shell runs batch files, so both the following lines work for me

IPC::Run::run(['C:/perl/5.10.1/bin/MSWin32-x86-multi-thread/perl.EXE',
+ qw! -e die(666) !]) ;
IPC::Run::run(['C:\perl\5.10.1\bin\MSWin32-x86-multi-thread\perl.EXE',
+ qw! -e die(666) !]) ;
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Interesting which cases work:

C:\>c:/windows/explorer

C:\>/windows/explorer

C:\>windows/explorer
'windows' is not recognized as an internal or external command,
operable program or batch file.

C:\>
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- tye        

Quotes almost always prevent the "/" from being treated as an option prefix.

C:\>"windows/explorer"

C:\>
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