(Feature Test Macros): Node moved off to creature.texi.

1 files changed, 3 insertions, 114 deletions

diff --git a/manual/intro.texi b/manual/intro.texi
index e698272d7c..9ca2ade9f8 100644
--- a/manual/intro.texi
+++ b/manual/intro.texi
@@ -515,120 +515,9 @@ The header file @file{termios.h} reserves names prefixed with @samp{c_},
 @pindex termios.h
 @end itemize
 
-
-@node Feature Test Macros,  , Reserved Names, Using the Library
-@subsection Feature Test Macros
-
-@cindex feature test macros
-The exact set of features available when you compile a source file
-is controlled by which @dfn{feature test macros} you define.
-
-If you compile your programs using @samp{gcc -ansi}, you get only the
-ANSI C library features, unless you explicitly request additional
-features by defining one or more of the feature macros.
-@xref{Invoking GCC,, GNU CC Command Options, gcc.info, The GNU CC Manual},
-for more information about GCC options.@refill
-
-You should define these macros by using @samp{#define} preprocessor
-directives at the top of your source code files.  These directives
-@emph{must} come before any @code{#include} of a system header file.  It
-is best to make them the very first thing in the file, preceded only by
-comments.  You could also use the @samp{-D} option to GCC, but it's
-better if you make the source files indicate their own meaning in a
-self-contained way.
-
-@comment (none)
-@comment POSIX.1
-@defvr Macro _POSIX_SOURCE
-If you define this macro, then the functionality from the POSIX.1
-standard (IEEE Standard 1003.1) is available, as well as all of the
-ANSI C facilities.
-@end defvr
-
-@comment (none)
-@comment POSIX.2
-@defvr Macro _POSIX_C_SOURCE
-If you define this macro with a value of @code{1}, then the
-functionality from the POSIX.1 standard (IEEE Standard 1003.1) is made
-available.  If you define this macro with a value of @code{2}, then both
-the functionality from the POSIX.1 standard and the functionality from
-the POSIX.2 standard (IEEE Standard 1003.2) are made available.  This is
-in addition to the ANSI C facilities.
-@end defvr
-
-@comment (none)
-@comment GNU
-@defvr Macro _BSD_SOURCE
-If you define this macro, functionality derived from 4.3 BSD Unix is
-included as well as the ANSI C, POSIX.1, and POSIX.2 material.
-
-Some of the features derived from 4.3 BSD Unix conflict with the
-corresponding features specified by the POSIX.1 standard.  If this
-macro is defined, the 4.3 BSD definitions take precedence over the
-POSIX definitions.
-
-Due to the nature of some of the conflicts between 4.3 BSD and POSIX.1,
-you need to use a special @dfn{BSD compatibility library} when linking
-programs compiled for BSD compatibility.  This is because some functions
-must be defined in two different ways, one of them in the normal C
-library, and one of them in the compatibility library.  If your program
-defines @code{_BSD_SOURCE}, you must give the option @samp{-lbsd-compat}
-to the compiler or linker when linking the program, to tell it to find
-functions in this special compatibility library before looking for them in
-the normal C library.
-@pindex -lbsd-compat
-@pindex bsd-compat
-@cindex BSD compatibility library.
-@end defvr
-
-@comment (none)
-@comment GNU
-@defvr Macro _SVID_SOURCE
-If you define this macro, functionality derived from SVID is
-included as well as the ANSI C, POSIX.1, and POSIX.2 material.
-@end defvr
-
-@comment (none)
-@comment GNU
-@defvr Macro _GNU_SOURCE
-If you define this macro, everything is included: ANSI C, POSIX.1,
-POSIX.2, BSD, SVID, and GNU extensions.  In the cases where POSIX.1
-conflicts with BSD, the POSIX definitions take precedence.
-
-If you want to get the full effect of @code{_GNU_SOURCE} but make the
-BSD definitions take precedence over the POSIX definitions, use this
-sequence of definitions:
-
-@smallexample
-#define _GNU_SOURCE
-#define _BSD_SOURCE
-#define _SVID_SOURCE
-@end smallexample
-
-Note that if you do this, you must link your program with the BSD
-compatibility library by passing the @samp{-lbsd-compat} option to the
-compiler or linker.  @strong{Note:} If you forget to do this, you may
-get very strange errors at run time.
-@end defvr
-
-We recommend you use @code{_GNU_SOURCE} in new programs.  If you don't
-specify the @samp{-ansi} option to GCC and don't define any of these macros
-explicitly, the effect is the same as defining @code{_GNU_SOURCE}.
-
-When you define a feature test macro to request a larger class of features,
-it is harmless to define in addition a feature test macro for a subset of
-those features.  For example, if you define @code{_POSIX_C_SOURCE}, then
-defining @code{_POSIX_SOURCE} as well has no effect.  Likewise, if you
-define @code{_GNU_SOURCE}, then defining either @code{_POSIX_SOURCE} or
-@code{_POSIX_C_SOURCE} or @code{_SVID_SOURCE} as well has no effect.
-
-Note, however, that the features of @code{_BSD_SOURCE} are not a subset of
-any of the other feature test macros supported.  This is because it defines
-BSD features that take precedence over the POSIX features that are
-requested by the other macros.  For this reason, defining
-@code{_BSD_SOURCE} in addition to the other feature test macros does have
-an effect: it causes the BSD features to take priority over the conflicting
-POSIX features.
+@comment Include the section on Creature Nest Macros.
+@comment It is in a separate file so it can be formatted into ../NOTES.
+@include creature.texi
 
 @node Roadmap to the Manual,  , Using the Library, Introduction
 @section Roadmap to the Manual