No need to call FindClose after FindNextFile failed?!

[programmer33]

Hi,

look at this piece of source from MSDN:

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/fileio/base/listing_the_files_in_a_directory.asp

They don't call FindClose if FindNextFile really failed (GetLastError()
!= ERROR_NO_MORE_FILES). Is that okay or is this a bug?

Bye

[Elias Fotinis]

programmer33 wrote:
> http://msdn.microsoft.com/library/default.asp?url=/library/en-us/fileio/base/listing_the_files_in_a_directory.asp
>
> They don't call FindClose if FindNextFile really failed
> (GetLastError() != ERROR_NO_MORE_FILES). Is that okay or is this a
> bug?

This is probably wrong code. You should always call FindClose for a
valid handle, no matter how the loop with FindNextFile ends:

HANDLE f = FindFirstFile(...);
if (f != INVALID_HANDLE_VALUE)
{
// FindNextFile loop
//...

FindClose(f);
}

[Lucian Wischik]

"Elias Fotinis" <efoti...@SPAMpat.forthnet.gr> wrote:
>HANDLE f = FindFirstFile(...);
>if (f != INVALID_HANDLE_VALUE)

>{ // FindNextFile loop ...
> FindClose(f);
>}

I've long wondered what the neatest idiom is for FindFile. I've ended
up with this:

HANDLE hf=FindFirstFile(...);
for (BOOL b=(hf!=INVALID_FILE_HANDLE); b; b=FindNextFile(hf))
{ ...
}
if (hf!=INVALID_FILE_HANDLE) FindClose(hf);

This way, it's compact, readable, non-nested, and 'continue' and
'break' statements within the loop are robust (in the sense that they
don't need accompanying FindNext/FindClose).

--
Lucian

[Alex Blekhman]

Lucian Wischik wrote:
> I've long wondered what the neatest idiom is for FindFile.

Alternatively you can wrap the logic in C++ class; similar to MFC's
CFindFile. Then it will be exception resistant, too.