Dear Perl Gurus,

I am writing a perl script to download files from internet using perl LWP , WWW::Mechanize modules. Currently I rely on HTTP_PROXY environment variable to understand the proxy. But it is pain to instruct the Windows users to set this variable and use my script.

I am thinking to find the HTTP proxy automatically and i was looking into MSDN and I found following windows APIs,

1. WinHttpGetProxyForUrl , http://msdn.microsoft.com/en-us/library/windows/desktop/aa384097(v=vs.85).aspx

2. InternetGetProxyInfo , http://msdn.microsoft.com/en-us/library/windows/desktop/aa384726(v=vs.85).aspx

I tried to use InternetGetProxyInfo API by using following code but looks like API itself is broken and suggestion is to use WinHttpGetProxyForUrl . 

use strict;
use warnings;
use Win32::Internet;

use Win32::API;

#$Win32::API::DEBUG = 1; 

my $InternetGetProxyInfo = Win32::API->new('jsproxy.dll', 'BOOL Intern
+etGetProxyInfo(LPCSTR lpszUrl, DWORD dwUrlLength, LPSTR lpszUrlHostNa
+me, DWORD dwUrlHostNameLength, LPSTR lplpszProxyHostName, LPDWORD lpd
+wProxyHostNameLength)') or warn "\n ERROR: Can not import API:i2cGetD
+eviceAddress ,  $^E ,";

my $lpszUrl = 'http://www.google.com';
my $dwUrlLength = length($lpszUrl);
my $lpszUrlHostName = 'www.google.com';
my $dwUrlHostNameLength = length($lpszUrlHostName);
my $lplpszProxyHostName = " " x 100;
my $lpdwProxyHostNameLength = 0;

print $InternetGetProxyInfo->Call($lpszUrl,$dwUrlLength,$lpszUrlHostNa
+me,$dwUrlHostNameLength,$lplpszProxyHostName,$lpdwProxyHostNameLength
+) or print "\n ERR: ",$^E;

print "\n ERR:", Win32::FormatMessage(Win32::GetLastError());

print "\n 1: $lplpszProxyHostName \n 2: $lpdwProxyHostNameLength \n";

[download]

Question: Any one tried this API in perl already? If so can you please point me some code reference? Or is there any better way to detect HTTP proxy automatically?

Thanks & Regards,
Bakki

Perl Gtk2 technology demo project - http://code.google.com/p/saaral-soft-search-spider/

In reply to How to Detect HTTP proxy settings automatically in Windows OS? by sam_bakki

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