How do I ignore the Perl shebang on Windows with Apache 2?

Question

I have set up a local Perl web environment on my Windows machine. The application I'm working on is originally from a Linux server, and so the shebang for source .pl files look like so:

#!/usr/bin/perl

This causes the following error on my Windows dev machine:

(OS 2)The system cannot find the file specified.

Is it possible to change my Apache 2 conf so that the shebang is ignored on my Windows machine? Of course I could set the shebang to #!c:\perl\bin\perl.exe, that much is obvious; but the problem comes to deploying the updated files. Clearly it would be very inconvenient to change this back on each deploy. I am using ActivePerl on Windows 7.

Update:

I should have mentioned that I need to keep the shebang so that the scripts will work on our shared hosting Linux production server. If I did not have this constraint and I didn't have to use the shebang, the obvious answer would be to just not use it.

Answer 1

I use #!/usr/bin/perl in my scripts and configure Apache on Windows to ignore the shebang line. Add

 ScriptInterpreterSource Registry-Strict

to your httpd.conf and set up the Windows Registry key as explained in the Apache docs.

Here is what I get when I export the key:

Windows Registry Editor Version 5.00

[HKEY_CLASSES_ROOT\.pl\Shell\ExecCGI\Command]
@="c:\\opt\\perl\\bin\\perl.exe"

I have been using this setup with Apache and ActiveState Perl on my Windows laptop and the Apache and Perl distributions that come with ArchLinux on my server.

The Apache docs (to which I linked above) state:

The option Registry-Strict which is new in Apache 2.0 does the same thing as Registry but uses only the subkey Shell\ExecCGI\Command. The ExecCGI key is not a common one. It must be configured manually in the windows registry and hence prevents accidental program calls on your system. (emphasis mine)

Answer 2

There is no portable shebang line. Even on the same platform and architecture, someone might have installed perl is a different location.

The trick is to not install modules and scripts by hand. When you package everything as distributions and use the module toolchain, the shebang lines are modified automatically to point to the perl you used to install everything. You shouldn't have to think about these details. :)

Answer 3

I use #! /usr/bin/env perl as the shebang on all of my perl, whether on *nix or Windows. Windows just ignores it, and the Unixen follow env to the chosen perl disto.

Answer 4

The way I had this working was to copy perl.exe to c:/usr/bin/ and rename it to perl (strip the .exe)

Answer 5

In win7 and up you can also do this with the "dos" command mklink.

Start a cmd shell as administrator and do something like the following:

mklink /d c:\usr c:\Perl       # Activestate perl in c:\Perl\bin\perl.exe
mklink /d c:\usr c:\xampp\perl # Xampp perl in c:\xampp\perl\bin\perl.exe

Answer 6

I don't have Windows handy, but perlcritic says:

my $desc = q{Found platform-specific perl shebang line};
my $expl = q{Perl source in parrot should use the platform-independent shebang line: #! perl};

So, I guess #! perl should work.

Edit: doesn't work on linux; apparently works in parrot, although I don't see how they manage that.

Answer 7

1. Install any Windows Bash flavor (such as Cygwin, MSYS2 or GnuWin32);

2. Create a trivial redirecting shell script:

   exec "@"
   

3. Create a registry entry:

   Windows Registry Editor Version 5.00
   
   [HKEY_CLASSES_ROOT\.cgi\Shell\ExecCGI\Command]
   @="<path-to-sh> <path-to-script>"
   
   [HKEY_CLASSES_ROOT\.pl\Shell\ExecCGI\Command]
   @="<path-to-sh> <path-to-script>"
   
   [HKEY_CLASSES_ROOT\.py\Shell\ExecCGI\Command]
   @="<path-to-sh> <path-to-script>"
   

   (...and so on.)

4. Jot in your httpd.conf file:

   ScriptInterpreterSource Registry
   

Apache will now resolve Unix shebangs relative to the interpretation given by your choosen Bash flavor. This gives much more flexibility than hardcoding interpreter paths in the registry.