doc: Omit internal modules from the "Undocumented modules" index

[Bruno Haible]

Some gnulib modules should not be mentioned in the "Undocumented modules" index,
because they are intentionally undocumented.


2024-12-29  Bruno Haible  <bruno@clisp.org>

        doc: Omit internal modules from the "Undocumented modules" index.
        * doc/internal-modules: New file.
        * doc/Makefile (undocumented-modules.texi): Filter out the internal
        modules.

diff --git a/doc/Makefile b/doc/Makefile
index 343419f44a..c7e505a6de 100644
--- a/doc/Makefile
+++ b/doc/Makefile
@@ -27,8 +27,10 @@ undocumented-modules.texi: force
        LC_ALL=C join -v1 all-modules.tmp documented-modules.tmp > 
undocumented-modules.tmp
 # For testing whether a module is deprecated, "./gnulib-tool --extract-status 
<module>" is a bit slow, so use grep instead.
        modules=`cat undocumented-modules.tmp`; (cd ../modules && grep -l 
'^deprecated$$' $$modules) > deprecated-undocumented-modules.tmp
-       LC_ALL=C join -v1 undocumented-modules.tmp 
deprecated-undocumented-modules.tmp | sed -e 's/^/@umindex /' > 
undocumented-modules.texi
-       rm -f documented-modules.tmp all-modules.tmp undocumented-modules.tmp 
deprecated-undocumented-modules.tmp
+       LC_ALL=C join -v1 undocumented-modules.tmp 
deprecated-undocumented-modules.tmp > undocumented-modules-2.tmp
+       LC_ALL=C join -v1 undocumented-modules-2.tmp internal-modules > 
undocumented-modules-3.tmp
+       sed -e 's/^/@umindex /' < undocumented-modules-3.tmp > 
undocumented-modules.texi
+       rm -f documented-modules.tmp all-modules.tmp undocumented-modules.tmp 
deprecated-undocumented-modules.tmp undocumented-modules-2.tmp 
undocumented-modules-3.tmp
 
 %.info: %.texi undocumented-modules.texi
        $(MAKEINFO) $(manual_opts) $<
diff --git a/doc/internal-modules b/doc/internal-modules
new file mode 100644
index 0000000000..63d0d5f722
--- /dev/null
+++ b/doc/internal-modules
@@ -0,0 +1,78 @@
+# This file lists the modules which are intentionally undocumented
+# because they are internal (i.e. only needed for the purpose of
+# other gnulib modules).
+#
+absolute-header
+at-internal
+dummy
+extensions-aix
+fd-hook
+gen-header
+gen-uni-tables
+glibc-internal/dynarray
+glibc-internal/scratch_buffer
+libc-config
+localename-unsafe
+localename-unsafe-limited
+mixin/printf-gnu
+mixin/printf-posix
+mktime-internal
+openat-die
+posix_spawn-internal
+setlocale-null-unlocked
+snippet/_Noreturn
+snippet/arg-nonnull
+snippet/c++defs
+snippet/link-warning
+snippet/unused-parameter
+snippet/warn-on-use
+socketlib
+strerror-override
+threadlib
+unicase/base
+unicase/cased
+unicase/ignorable
+unicase/special-casing
+unicase/tocasefold
+unicase/u16-casemap
+unicase/u16-is-invariant
+unicase/u32-casemap
+unicase/u32-is-invariant
+unicase/u8-casemap
+unicase/u8-is-invariant
+uniconv/base
+unictype/category-none
+unigbrk/base
+unilbrk/base
+unilbrk/tables
+unilbrk/ulc-common
+unimetadata/base
+unimetadata/u-version
+uniname/base
+uninorm/compat-decomposition
+uninorm/decompose-internal
+uninorm/decomposition-table
+unistdio/base
+unistdio/u-printf-args
+unistdio/u16-printf-parse
+unistdio/u32-printf-parse
+unistdio/u8-printf-parse
+unistdio/ulc-printf-parse
+unistr/base
+uniwbrk/base
+uniwbrk/table
+uniwidth/base
+unlocked-io-internal
+windows-cond
+windows-mutex
+windows-once
+windows-recmutex
+windows-rwlock
+windows-spawn
+windows-spin
+windows-stat-override
+windows-thread
+windows-timedmutex
+windows-timedrecmutex
+windows-timedrwlock
+windows-tls