Re: [Boost-build] --exec-prefix --builddir and --build-dir

From: David Abrahams (dave_at_[hidden])
Date: 2006-11-29 16:25:00

Rene Rivera <grafikrobot_at_[hidden]> writes:

> David Abrahams wrote:
>> If you look at 
>> 
>>   bjam --v2 --help
>> 
>> you'll see a mix of option styles.  There's 
>> 
>>      --exec-prefix
>> 
>> with two words separated by a hyphen, but there's also
>> 
>>      --builddir
>> 
>> and
>>      
>>      --buildid
>> 
>> I believe --builddir is especially heinous because, IIUC, the
>> official BBv2 option is --build-dir. 
>
> <sracasm> Welcome to the wonderful world of autoconf options. </sarcasm>
>
> The "--exec-prefix" is what autoconf uses. And the "--builddir" follows 
> the autoconf style for things like "--bindir", "--datadir", etc:
>
> Fine tuning of the installation directories:
>    --bindir=DIR           user executables [EPREFIX/bin]
>    --sbindir=DIR          system admin executables [EPREFIX/sbin]
>    --libexecdir=DIR       program executables [EPREFIX/libexec]
>    --datadir=DIR          read-only architecture-independent data 
> [PREFIX/share]
>    --sysconfdir=DIR       read-only single-machine data [PREFIX/etc]
>    --sharedstatedir=DIR   modifiable architecture-independent data 
> [PREFIX/com]
>    --localstatedir=DIR    modifiable single-machine data [PREFIX/var]
>    --libdir=DIR           object code libraries [EPREFIX/lib]
>    --includedir=DIR       C header files [PREFIX/include]
>    --oldincludedir=DIR    C header files for non-gcc [/usr/include]
>    --infodir=DIR          info documentation [PREFIX/info]
>    --mandir=DIR           man documentation [PREFIX/man]

I should've known :(

>> This is making it hard for me to
>> give clear and straightforward getting started instructions. 
>
> Yea, clarity, one of the reasons I hate autoconf.

Me too.

>> Can we please settle on one convention?  I prefer (by far) the
>> versions with the hyphens.
>
> Sure... But do we want to stray from the insistent users familiar with 
> autoconf options?

Nope :(

>> If there's some need to keep the un-hyphenated options for backward
>> compatibility, can we at least make them undocumented?
>
> The only backward compatibility would be the configure script (not that 
> it works as is anyway), 

Needs to be fixed, then.

> and possible user scripts. The former can be fixed, the latter is
> more problematic, but since users would likely need to change such
> scripts to account for the rest of the new BBv2 syntax I wouldn't
> worry too much about it.

Right.  I think we'd better keep the autoconf options for our
configure script... maybe it makes sense to keep them for Boost.Build
as well, but simply document them as an allowed alternative.  I
actually think that accepting both forms will make the tool easier to
use, since I've very often dropped or added hyphens to configure
scripts and gotten the wrong results.

-- 
Dave Abrahams
Boost Consulting
www.boost-consulting.com