RE: [boost] [ boost-Bugs-1164057 ]boost::filesystem::exists has b ugs with UNC paths

From: Beman Dawes (bdawes_at_[hidden])
Date: 2005-03-17 20:58:03

At 11:59 AM 3/17/2005, Martin Bonner wrote:
 >----Original Message----
 >From: Robert Mathews [mailto:rmathews_at_[hidden]]
 >Sent: 17 March 2005 14:56
 >To: boost_at_[hidden]
 >Subject: [boost] Re: [Boost-bugs] [ boost-Bugs-1164057
 >]boost::filesystem::exists has bugs with UNC paths
 >
 >>> Initial Comment:
 >>> boost::filesystem::exists(path("//computer")) always
 >>> fails, even if the computer exists.
 >
 >I shall call this, Issue A.
 >
 >>> boost::filesystem::exists(path("//computer/share"))
 >>> always succeeds, even if the share doesn't exist.
 >
 >... and this Issue B.
 >
 >> Can anyone actually comment on when or if this bug might actually get
 >> fixed? It's an obvious bug, the fix is a trivial amount of work - it
 >> comes with a patch that I've tested on Win32 ....
 >
 >Well, as I have indicated above, there are two separate and distinct
 >issues.

Yes.

 >Issue B does seem like a bug to me.  On the other hand, does your fix
 >change
 >it so that //computer/printer is reported as a filesystem?  That would be 
a
 >step backwards.

A true return from exists() doesn't make any claim that the path is to a 
filesystem. Consider this program:

#include <iostream>
#include <fstream>

int main( int argc, char * argv[] )
{
   std::ofstream os( argv[1] );
   if ( !os )
   {
     std::cout << "Could not open " << argv[1] << std::endl;
     return 1;
   }
   os << "Hello, printer!\n";
   return 0;
}

The network name of my machine is "bgd". It has a shared printer named 
"NECSuper". If I invoke the above program (named "test") like this:

    >test \\bgd\NECSuper

A page gets printed with text: "Hello, printer!"

And:

    >test con:
    Hello, printer!

But:

    >test \\bgd
    Could not open \\bgd

    >test \\bgd\no_such
    Could not open \\bgd\no_such

So I would likewise expect calls to exists("//bgd/NECSuper" ) and 
exists("con:") to return true, and a call to exists("//bgd/no_such") to 
return false.

My initial feeling about exists("//bgd") is that it should return false, 
but I'm not very sure about that one and would like to hear more opinions.

Thanks for the comments,

--Beman