DWORD GetShortPathName(
  LPCTSTR lpszLongPath,  // null-terminated path string
  LPTSTR lpszShortPath,  // short form buffer
  DWORD cchBuffer        // size of short form buffer
);

##</code><code>##

use Win32::API;

#import the function
my $GetShortPathName = new Win32::API("kernel32","GetShortPathName",[ P,P,N ],N);


if (not defined $GetShortPathName) {
	die "could not import GetShortPathName";
}

#the name we want to convert
$longname = "C:\\Program Files\\Microsoft Office\\Office\\OLREAD9.TXT";

#create a string big enough to hold the shortname
$shortname = " " x 80;

#retval will be length of the DOSified short name
$retval = $GetShortPathName->Call($longname,$shortname,80);

#trim the trailing blanks
#recall that $shortname = " " x 80
#and retval is the length of the name returned by GetShortPathName
$shortname = substr($shortname,0,$retval);

print "longname = \n\"$longname\", \nshortname = \n\"$shortname\"";

##</code><code>##

C:\temp>perl shortname.pl
longname =
"C:\Program Files\Microsoft Office\Office\OLREAD9.TXT",
shortname =
"C:\PROGRA~1\MICROS~3\Office\OLREAD9.TXT"
C:\temp>