Perl for Win32 Frequently Asked Questions (FAQ)

9.1. Many of the scripts/modules in my perl5/Lib directory don't work. Why not?

These modules are distributed AS-IS, without any guarantee to work. There are a couple of reasons why a module won't work:

• it uses a function not provided by Perl for Win32
• it uses a UNIX tool that's not available on Win32 platforms
• it makes assumptions about the way files are handled that aren't valid on Win32 platforms

There are a couple of extensions that have been developed to access databases from Perl for Win32. Win32::ODBC is widely popular, and is available on CPAN and at this URL:

Yes. You can read all about this on the oleauto page in the Perl for Win32 documentation. There are two examples of using Perl for Win32 to access Microsoft Excel in the eg subdirectory of your perl directory.

Note that this is only OLE Automation, and that you can't do other OLE things like embed documents or provide drag-and-drop, etc. Also, note that, because of a bug in the OLE code, you can't use any OLE server that is implemented as a DLL (they use CLSCTX_LOCAL_SERVER for CoCreateInitialize rather than CLSCTX_SERVER, if that makes any sense to you).

Currently, there's no direct way to access MAPI from Perl scripts. Efforts are underway to create a Perl extension to do simple MAPI functions. Keep an eye on this space for more details.

[Is this right? Are there any MAPI extensions out there? -ESP]

Yes, there is. SDBM_File is a free clone of DBM, and is implemented and distributed with the Perl for Win32 distribution. You can use it as follows:

So far, not yet. The TK library has been ported to Win32 operating systems, however, so we should expect a perlTK port at some point. If you need it, maybe you should work on porting it. Information on this can be found in the perl/Tk distribution on CPAN.

Along with the standard library files, there are several Win32-specific modules that are distributed with Perl for Win32. These include:

• Win32::ChangeNotification: Create and use ChangeNotification objects [whatever the heck those are... -ESP]
• Win32::EventLog: Read from and write to the Windows NT event log
• Win32::File: Manage file attributes (read only, system, hidden...)
• Win32::IPC: Wait for objects (processes, mutexes, semaphores)
• Win32::Mutex: Create and use mutexes
• Win32::NetAdmin: Administer users and groups
• Win32::NetResource: Manage resources (servers, file shares, printers)
• Win32::Process: Start and stop Win32 processes
• Win32::Registry: Read and manage the Win32 registry
• Win32::Semaphore: Create and use semaphores
• Win32::Service: Manage Windows NT services
• Win32::Timer: For getting millisecond-level timing information
• Win32::WinError: For retrieving Win32-defined errors

These are documented on the Win32mod documentation page. There are also a number of subs built into the Win32 package, namely:

• GetLastError: Retrieve the last Win32 error code.
• PerlVersion: What version of Perl for Win32 is this?
• LoginName: Name of logged-in user [? -ESP]
• NodeName: Name of this machine [? -ESP]
• DomainName: Name of the domain this machine is in [? -ESP]
• FsType: Get the file system type of a drive
• GetCwd: Get current working directory [? -ESP]
• SetCwd: Set " " " [? -ESP]
• GetOSVersion: Get Win32 operating system version [? -ESP]
• FormatMessage: Format a Win32 error code into a [localized? -ESP] error message
• Spawn: Spawn a Win32 process
• LookupAccountName: Given a user name, get domain, SID, SID type
• LookupAccountSID: Given a SID, get domain, user name, SID type
• InitiateSystemShutdown: Shut down this computer
• AbortSystemShutdown: I mean, don't shut down this computer
• GetTickCount: Time since Windows started, in milliseconds (for timing)
• IsWinNT: Is this Windows NT?
• IsWin95: Or, is it Windows 95?
• GetArchName: What chip architecture (Intel, Alpha, PowerPC, MIPS)
• GetChipName: What chip name [? -ESP]
• ExpandEnvironmentStrings: Take a string like %HOMEPATH% and expand it to the actual value [? -ESP]

[Can anyone straighten me out on some of these? -ESP]

Modules for Perl for Win32 are available on CPAN (Comprehensive Perl Archive Network), a Perl archive that's mirrored around the world. To find your nearest mirror, check here:

Yes, a port of GD, Win32GD, is available at the following URL:

The Fcntl module (for file control flags) is not included in the binary distributions of Perl for Win32. You need to get the source distribution, and build the Fcntl module yourself.

[Thanks to Dave Wolfe (dwolfe@risc.sps.mot.com) for this answer. -ESP]

File::Find is the Perl 5 module for directory tree recursion; find.pl and finddepth.pl are the Perl 4 versions of those functions, and have been adapted for use with the Perl for Win32 system. Cwd is used to change the working directory.

The File::Find distributed with build 110 has a number of problems in the way the communication variables (i.e. $dont_use_nlink, $prune, $name, and $dir) are declared and other packages are called.

File::Find also uses return values from the stat command to determine where it is in the directory hierarchy. Since MS file systems don't use the concept of inodes and links to identify files, the "number of links" field (aka nlinks) for a directory has no meaning for them. Later versions of Find.pm use the OS name from Config.pm to decide whether or not to use nlinks.

Finally, File::Find depends on the faulty Cwd.pm.

For build 110, the following procedure will make File::Find and Cwd workable:

CPAN is the Comprehensive Perl Archive Network, a collection of pretty much every file you could ever want for Perl programming. The original archive is in Finland, but it is mirrored on FTP servers throughout the world.

You can connect to your "closest" CPAN mirror using the CPAN redirector at www.perl.com. The following URL:

In general, there aren't any library modules to read or write application files, like Microsoft Word, Microsoft Excel, Microsoft Access, WordPerfect, Lotus 1-2-3, etc.