X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=doc%2Fgnulib.texi;h=ee04e2a7523024a1dc7c89e517663fa12d87ba66;hb=a83a25fd19a04a9ec3dedd34f7e36c4cefe6f8ca;hp=62f969ed1791a361aa0a80fb1ba17c3c6c219ef6;hpb=f62e9d92ff548d8671fef70f42d1a173933cceb5;p=gnulib.git diff --git a/doc/gnulib.texi b/doc/gnulib.texi index 62f969ed1..ee04e2a75 100644 --- a/doc/gnulib.texi +++ b/doc/gnulib.texi @@ -2,8 +2,14 @@ @comment %**start of header @setfilename gnulib.info @settitle GNU Gnulib +@c Define a new index for the magic constants in regex.texi. +@defcodeindex cn @syncodeindex fn cp +@syncodeindex ky cp @syncodeindex pg cp +@syncodeindex tp cp +@syncodeindex vr cp +@syncodeindex cn cp @ifclear texi2html @firstparagraphindent insert @end ifclear @@ -54,6 +60,7 @@ Documentation License''. * Introduction:: * Invoking gnulib-tool:: * Writing modules:: +* Extending Gnulib:: * Miscellaneous Notes:: * POSIX Substitutes Library:: Building as a separate substitutes library. * Header File Substitutes:: Overriding system headers. @@ -62,6 +69,7 @@ Documentation License''. * Glibc Header File Substitutes:: Overriding system headers. * Glibc Function Substitutes:: Replacing system functions. * Particular Modules:: Documentation of individual modules. +* Regular expressions:: The regex module. * GNU Free Documentation License:: Copying and sharing this manual. * Index:: @end menu @@ -117,8 +125,8 @@ Resources: @node Writing modules @chapter Writing modules -This chapter explains how to write modules of your own, either for your own -package (to be used with gnulib-tool's @samp{--local-dir} option), or for +This chapter explains how to write modules of your own, either to +extend Gnulib for your own package (@pxref{Extending Gnulib}), or for inclusion in gnulib proper. The guidelines in this chapter do not necessarily need to be followed for @@ -608,6 +616,84 @@ before every release. @end enumerate +@node Extending Gnulib +@chapter Extending Gnulib + +Gnulib modules are intended to be suitable for widespread use. Most +problems with Gnulib can and should be fixed in a generic way, so that +all of Gnulib's users can benefit from the change. But occasionally a +problem arises that is difficult or undesirable to fix generically, or +a project that uses Gnulib may need to work around an issue before the +Gnulib maintainers commit a final fix. Maintainers may also want to +add their own pools of modules to projects as Gnulib ``staging +areas.'' + +The obvious way to make local changes to Gnulib modules is to use +@command{gnulib-tool} to check out pristine modules, then to modify +the results in-place. This works well enough for short-lived +experiments. It is harder to keep modified versions of Gnulib modules +for a long time, even though Git (or another distributed version +control systems) can help out a lot with this during the development +process. + +Git, however, doesn't address the distribution issue. When a package +``foobar'' needs a modified version of, say, @file{stdint.in.h}, it +either has to put a comment into @file{foobar/autogen.sh} saying +``Attention! This doesn't work with a pristine Gnulib, you need this +and that patch after checking out Gnulib,'' or it has to use the +@samp{--avoid=stdint} option and provide the modified @code{stdint} +module in a different directory. + +The @option{--local-dir} option to @command{gnulib-tool} solves this +problem. It allows the package to override or augment Gnulib. This +means: + +@itemize @bullet +@item +You can store files that are to override Gnulib files or modules. + +@item +You can store context diffs to be applied to Gnulib files. + +@item +You can add modules of your own, that are not (yet) in Gnulib. + +@item +You can also add unstructured amounts of code to the library, by +grouping the non-Gnulib files of the library in a single kitchen-sink +``module.'' (This kind of kitchen-sink module is not needed when you +use the @command{gnulib-tool} option @samp{--makefile-name}.) +@end itemize + +In a release tarball, you can distribute the contents of this +@option{--local-dir} directory that will be combinable with newer +versions of Gnulib, barring incompatible changes to Gnulib. + +If the @samp{--local-dir=@var{directory}} option is specified, then +@command{gnulib-tool} looks in @file{@var{directory}} whenever it +reads a file from the Gnulib directory. Suppose @command{gnulib-tool} +is looking for @var{file}. Then: + +@itemize @bullet +@item +If @file{@var{directory}/@var{file}} exists, then @samp{gnulib-tool} uses +it instead of the file included in Gnulib. + +@item +Otherwise, if @file{@var{directory}/@var{file}.diff} exists, then +@command{gnulib-tool} uses the file from Gnulib after applying the diff +using the @command{patch} program. + +@item +Otherwise, @command{gnulib-tool} uses the file included in Gnulib. +@end itemize + +Please make wise use of this option. It also allows you to easily +hold back modifications you make to Gnulib macros in cases it may be +better to share them. + + + @node Miscellaneous Notes @chapter Miscellaneous Notes @@ -6407,7 +6493,6 @@ This list of functions is sorted according to the header that declares them. * Quoting:: * error and progname:: * gcd:: -* Regular expressions:: * Searching for Libraries:: * Exported Symbols of Shared Libraries:: * LD Version Scripts:: @@ -6416,6 +6501,7 @@ This list of functions is sorted according to the header that declares them. * func:: * warnings:: * manywarnings:: +* Running self-tests under valgrind:: @end menu @node alloca @@ -6488,16 +6574,6 @@ ASCII characters. @include gcd.texi -@node Regular expressions -@section Regular expressions - -Gnulib supports many different types of regular expressions; although -the underlying features are the same or identical, the syntax used -varies. The descriptions given here for the different types are -generated automatically. - -@include regexprops-generic.texi - @include havelib.texi @include lib-symbol-visibility.texi @@ -6514,6 +6590,36 @@ generated automatically. @include manywarnings.texi +@include valgrind-tests.texi + +@node Regular expressions +@chapter Regular expressions + +@menu +* Overview:: +* Regular Expression Syntax:: +* Common Operators:: +* GNU Operators:: +* GNU Emacs Operators:: +* What Gets Matched?:: +* Programming with Regex:: +* Regular expression syntaxes:: +@end menu + +@lowersections +@include regex.texi +@raisesections + +@node Regular expression syntaxes +@section Regular expression syntaxes + +Gnulib supports many different types of regular expressions; although +the underlying features are the same or identical, the syntax used +varies. The descriptions given here for the different types are +generated automatically. + +@include regexprops-generic.texi + @node GNU Free Documentation License @appendix GNU Free Documentation License