diff options
Diffstat (limited to 'doc')
| -rw-r--r-- | doc/make.texi | 77 |
1 files changed, 57 insertions, 20 deletions
diff --git a/doc/make.texi b/doc/make.texi index 3a16dd3..f5ca116 100644 --- a/doc/make.texi +++ b/doc/make.texi @@ -4,7 +4,6 @@ @include version.texi @set EDITION 0.72 -@set RCSID $Id$ @settitle GNU @code{make} @setchapternewpage odd @@ -27,7 +26,7 @@ of @cite{The GNU Make Manual}, for GNU @code{make} version @value{VERSION}. Copyright @copyright{} 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2002, 2003, 2004, 2005, 2006, 2007, -2008, 2009, 2010, 2011, 2012 Free Software Foundation, Inc. +2008, 2009, 2010, 2011, 2012, 2013 Free Software Foundation, Inc. @quotation Permission is granted to copy, distribute and/or modify this document @@ -348,6 +347,7 @@ GNU Guile Integration Loading Dynamic Objects * load Directive:: Loading dynamic objects as extensions. +* Remaking Loaded Objects:: How loaded objects get remade. @end detailmenu @end menu @@ -1287,7 +1287,6 @@ in the makefiles. @xref{Include, , Including Other Makefiles}. @node Remaking Makefiles, Overriding Makefiles, MAKEFILES Variable, Makefiles @section How Makefiles Are Remade - @cindex updating makefiles @cindex remaking makefiles @cindex makefile, remaking of @@ -6295,7 +6294,6 @@ Has GNU Guile available as an embedded extension language. @item load Supports dynamically loadable objects for creating custom extensions. @xref{Loading Objects, ,Loading Dynamic Objects}. - @end table @vindex .INCLUDE_DIRS @r{(list of include directories)} @@ -10539,11 +10537,11 @@ program, although this can be inefficient. In cases where the built-in capabilities of GNU @code{make} are insufficient to your requirements there are two options for extending @code{make}. On systems where it's provided, you can utilize GNU -Guile as an embedded scripting language (@pxref{Guile Integration, -,GNU Guile Integration}). On systems which support dynamically -loadable objects, you can write your own extension in any language -(which can be compiled into such an object) and load it to provide -extended capabilities (@pxref{load Directive, ,The @code{load} Directive}). +Guile as an embedded scripting language (@pxref{Guile Integration,,GNU +Guile Integration}). On systems which support dynamically loadable +objects, you can write your own extension in any language (which can +be compiled into such an object) and load it to provide extended +capabilities (@pxref{load Directive, ,The @code{load} Directive}). @menu * Guile Integration:: Using Guile as an embedded scripting language. @@ -10786,15 +10784,16 @@ providing new capabilities which may then be invoked by your makefile. The @code{load} directive is used to load a dynamic object. Once the object is loaded, a ``setup'' function will be invoked to allow the object to initialize itself and register new facilities with GNU -@code{make}. Typically a dynamic object would create new functions, +@code{make}. A dynamic object might include new @code{make} functions, for example, and the ``setup'' function would register them with GNU @code{make}'s function handling system. @menu * load Directive:: Loading dynamic objects as extensions. +* Remaking Loaded Objects:: How loaded objects get remade. @end menu -@node load Directive, , Loading Objects, Loading Objects +@node load Directive, Remaking Loaded Objects, Loading Objects, Loading Objects @subsection The @code{load} Directive @cindex load directive @cindex extensions, load directive @@ -10814,21 +10813,33 @@ or: load @var{object-file}(@var{symbol-name}) @dots{} @end example -In the first form, the file @var{object-file} is dynamically loaded by -GNU @code{make}. On failure, @code{make} will print a message and -exit. If the load succeeds @code{make} will invoke an initializing -function whose name is created by taking the base file name of -@var{object-file}, up to the first character which is not a valid -symbol name character (alphanumerics and underscores are valid symbol -name characters). To this prefix will be appended the suffix -@code{_gmake_setup}, then this symbol will be invoked. +The file @var{object-file} is dynamically loaded by GNU @code{make}. +If @var{object-file} does not include a directory path then it is +first looked for in the current directory. If it is not found there, +or a directory path is included, then system-specific paths will be +searched. If the load fails for any reason, @code{make} will print a +message and exit. + +If the load succeeds @code{make} will invoke an initializing function. + +If @var{symbol-name} is provided, it will be used as the name of the +initializing function. -In the second form, the function @var{symbol-name} will be invoked. +If no @var{symbol-name} is provided, the initializing function name is +created by taking the base file name of @var{object-file}, up to the +first character which is not a valid symbol name character +(alphanumerics and underscores are valid symbol name characters). To +this prefix will be appended the suffix @code{_gmake_setup}. More than one object file may be loaded with a single @code{load} directive, and both forms of @code{load} arguments may be used in the same directive. +The initializing function will be provided the file name and line +number of the invocation of the @code{load} operation. It should +return a value of type @code{int}, which must be @code{0} on failure +and non-@code{0} on success. + For example: @example @@ -10864,6 +10875,22 @@ generated if an object fails to load. The failed object is not added to the @code{.LOADED} variable, which can then be consulted to determine if the load was successful. +@node Remaking Loaded Objects, , load Directive, Loading Objects +@subsection How Loaded Objects Are Remade +@cindex updating load objects +@cindex remaking load objects +@cindex load objects, remaking of + +Loaded objects undergo the same re-make procedure as makefiles +(@pxref{Remaking Makefiles, ,How Makefiles Are Remade}). If any +loaded object is recreated, then @code{make} will start from scratch +and re-read all the makefiles, and reload the object files again. It +is not necessary for the loaded object to do anything special to +support this.@refill + +It's up to the makefile author to provide the rules needed for +rebuilding the loaded object. + @node Features, Missing, Extending make, Top @chapter Features of GNU @code{make} @cindex features of GNU @code{make} @@ -11007,6 +11034,12 @@ nonexistent file comes from SunOS 4 @code{make}. (But note that SunOS 4 The @code{!=} shell assignment operator exists in many BSD of @code{make} and is purposefully implemented here to behave identically to those implementations. + +@item +Various build management tools are implemented using scripting +languages such as Perl or Python and thus provide a natural embedded +scripting language, similar to GNU @code{make}'s integration of GNU +Guile. @end itemize The remaining features are inventions new in GNU @code{make}: @@ -11116,6 +11149,10 @@ Various new built-in implicit rules. The built-in variable @samp{MAKE_VERSION} gives the version number of @code{make}. @vindex MAKE_VERSION + +@item +Load dynamic objects which can modify the behavior of @code{make}. +@xref{Loading Objects, ,Loading Dynamic Objects}. @end itemize @node Missing, Makefile Conventions, Features, Top |