Re: [boost] [filesystem] dirent::d_type extension availability?

From: Neal Becker (ndbecker2_at_[hidden])
Date: 2005-12-17 07:33:33

Neal Becker wrote:

> Beman Dawes wrote:
> 
>> The directory iterator value type objects now caches status information.
>> Performance is much better (6 times, in one test).
>> 
>> This optimization is present for the Windows API, and for POSIX systems
>> which support the BSD dirent::d_type extension. Currently this is
>> detected by the __USE_BSD macro. Please report other macros which
>> indicate it is safe to turn on this feature.
>> 
>> IIRC, someone indicated that Linux also supports the feature, but
>> perhaps only on later versions. If that is the case, what is the correct
>>   macros to be tested for what values?
>> 

To be more precise: this is not a feature of Linux - it's a feature of the c
lib.  Linux systems ususally use glibc, but small embedded systems may use
other clibs, such as ulibc.  This is why lots of people gave up on "guess
the macro" years ago and changed to some kind of autoconf.  There are too
many variables.