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Subject: Re: [boost] [guideline] 31 character filenames?
From: Dave Abrahams (dave_at_[hidden])
Date: 2012-03-30 18:18:17

on Wed Mar 28 2012, Beman Dawes <> wrote:

> On Wed, Mar 28, 2012 at 4:44 AM, Paul A. Bristow
> <pbristow_at_[hidden]> wrote:
>> As I recall, the 31 char limit was because we wanted to be able to
>> copy all the files on a CD.
> IIRC, there were still some users on old Macs with a 31 char limit on
> hard disk filenames.
>> I'm not sure this is still important (you'd probably zip anyway?),
>> so I agree it should be dropped
>> as a requirement, and the bugs 'won't-fixed'.
>> I've had Doxygen generated filenames that were too long (for
>> Windows?)  and had to use the mechanism
>> provided to make them shorter, so I think we need to keep that (preferably bug-free ;-)
> Windows maximum for a directory or file name depends on the particular
> file system, but is typically 255 characters. Looking at
>, 255 seems a
> pretty typical limit for modern file systems.
> Windows maximum for a path is 32,767 Unicode characters in theory, but
> a path longer than 260 (I.E. MAX_PATH) requires special syntax so
> that's a practical limit for some uses.
> There is also the question of readability and usability. At some
> point, really long file names are an irritation, even if not
> technically illegal.
> So perhaps we might bump the limit at bit, but let's not get too extreme.

Wasn't this limit related to what could be encoded on an ISO CD/DVD or
something? That's my recollection.

Dave Abrahams
BoostPro Computing

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