[OS X TeX] Finally we are grown up

[Martin Costabel]

Gerben Wierda wrote:
> On Nov 18, 2006, at 03:21, Enrico Franconi wrote:
> 
>> The lack of dependencies' maintenance in the i-installer is what made 
>> me choose fink (with its GUI, FinkCommander), and now darwinports 
>> (with its GUI, PortAuthority) to install libraries and binaries other 
>> than the TeX distribution. If you have a complex unix system, you can 
>> not simply upgrade/uninstall a library without checking whether this 
>> has been used by other stuff, which may depend on it or on a 
>> particular version of it.

I think Enrico raises a very valid point here. The i-installer adheres, 
like many contributors to this list, basically to a "single application" 
philosophy. For a student writing his PhD thesis or someone occupied for 
years by his Opus Magnum, this is legitimate; they will use their 
computer, besides doing their E-Mail and browsing the web, essentially 
for one other application, in this case TeX. But for many others, the 
"single application" approach belongs to the list of "single tasking" 
and "single user" that were once valid for Mac users and still are to a 
certain extent, but should not be accepted any more as a principle.

> There are several strategies possible here. Fink & Darwinports follow 
> the "splendid isolation" strategy. This enables them to have more 
> control. i-Installer installs what is the result of downloaidng and 
> compiling from source and installing in its default place (generally).

It is all very nice mingling with the crowd if the crowd consists 
essentially of yourself and your family. As soon as strangers get in, 
things quickly become much less cosy. Enrico mentioned the problem of 
dependency on a particular version of a library, and this is impossible 
to solve if several third-party applications install their libraries in 
the same default places /usr/local/lib and /Library. These default 
places rather quickly become ugly garbage dumps where after a while you 
don't even know where the things came from that you find there.

> i-Installer has dependencies handling (both required and recommended) 
> and you will get warnings about the inavailability of required dynamic 
> libraries. The funny thing is that it does not matter to the user if 
> these libraries have been installed by i-Installer or any other system 
> (like downloading and compiling by hand). i-Installer will perfectly 
> detect the availability of freetype as a prerequisite for ImageMagick 
> but it does not force you to use i-Installer in installing this.

This is all very nice in an ideal world where there is only one version 
of libfreetype, or where different versions of libfreetype are 
compatible with each other. In the real world this is not the case. As 
an example, here are two reasons why your dependency control may be 
insufficient as soon as there is some other application that installs 
freetype in the same default places as the i-installer:

- If your ImageMagick is linked against a certain version of 
libfreetype, then replacing that version of libfreetype by one with a 
lower compatibility version (although the main library version may be 
the same) will make the ImageMagick binaries crash. Replacing it with a 
later version may or may not work, depending on backward compatibility 
of the new library (and backward compatibility was not one of the strong 
points of freetype2 in the past). Likewise, installing libfreetype with 
i-installer may make other applications crash that are expecting a 
different version in the default places.

- The current release 2.2.1 of freetype2 is broken on OSX/Intel when the 
old-mac-fonts feature is activated. A patch is known, and you may be 
incorporating it into your release or not, I don't know. But if some 
other application or a standalone install of freetype2 installs the 
"official" libfreetype-2.2.1, you will get crashes that you cannot control.

>> If you use your computer in several different ways, the i-installer 
>> may disrupt in a very subtle way your system.
[]
>> It seems to me that the i-installer is very good at its job for users 
>> who do not install any other library in any other way.
> 
> The philosophy of i-Installer is the opposite, see dependency example 
> above.

To overcome the "single application" restriction, there exist only two 
possibilities on the Mac:

Either one uses app-bundles for everything, where all required libraries 
are always stored inside the bundle. Every application that needs 
libfreetype will then install its own copy in its own private place. 
This is the NextStep/OSX standard way, ideally suited for commercial 
software or shareware. It is also a huge waste of resources.

Or one uses a package manager like Fink or MacPorts (FKA DarwinPorts) to 
control everything outside of the system. This is similar to what every 
Linux distribution is doing. It is also where i-installer seemed to be 
heading recently ("everything" then meaning "everything a typical latex 
user might be interested in"), but it is much too big a task for a 
single person to manage, it needs a community of developers.

-- 
Martin


------------------------- Info --------------------------
Mac-TeX Website: http://www.esm.psu.edu/mac-tex/
          & FAQ: http://latex.yauh.de/faq/
TeX FAQ: http://www.tex.ac.uk/faq
List Archive: http://tug.org/pipermail/macostex-archives/