1 Libidn FAQ -- Anticipated Frequently Asked Questions.
2 Copyright (C) 2002, 2003 Simon Josefsson
3 See the end for copying conditions.
5 Q#1: Why doesn't Libidn use a separate library for the Unicode
8 A#1: Separate libraries (Glib, QT, libiconv) seldom mark the
9 Unicode tables with the corresponding Unicode version they
10 implement, nor do they provide a interface where a specific
11 version can be requested. This violates the stringprep
12 specification which requires that a specific version must be
13 used. Also, some of these third party libraries depend on
14 non-portable behavior (e.g. threads).
16 Q#2: Why do Libidn include several stringprep profiles? They waste
19 A#2: The stringprep profiles included are usually derived from the
20 generic stringprep tables, and doesn't waste more than say a few
21 hundred bytes (see profiles.c). The Unicode normalization tables
22 and the generic stringprep tables are roughly equivalent in size,
23 although the latter tables can surely be compressed much further.
24 However, if in the future several large Stringprep profiles are
25 added, configure options will be added to help reduce size.
27 Q#3: I thought GNU was encouraging libraries to be licensed under the GPL?
29 A#3: The reasoning for this was for libraries that provide unique
30 functionality to encourage more free programs. Since there are
31 several IDN libraries out there, using the GPL for Libidn would
32 only encourage people not to use Libidn which would not help the
33 spread of free software.
35 Q#4: How do I add a new stringprep profile?
37 A#4: Add the profile definition to profiles.c, export the symbol and
38 optionally add a CPP macro in stringprep.h.in (and document it in
39 stringprep.c). If you want to add self tests, do it through
40 tst_stringprep.c. Mention it in NEWS.
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