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diff --git a/system/doc/extensions/include.xml b/system/doc/extensions/include.xml deleted file mode 100644 index cd78644b95..0000000000 --- a/system/doc/extensions/include.xml +++ /dev/null @@ -1,81 +0,0 @@ -<?xml version="1.0" encoding="latin1" ?> -<!DOCTYPE chapter SYSTEM "chapter.dtd"> - -<chapter> - <header> - <copyright> - <year>1999</year><year>2009</year> - <holder>Ericsson AB. All Rights Reserved.</holder> - </copyright> - <legalnotice> - The contents of this file are subject to the Erlang Public License, - Version 1.1, (the "License"); you may not use this file except in - compliance with the License. You should have received a copy of the - Erlang Public License along with this software. If not, it can be - retrieved online at http://www.erlang.org/. - - Software distributed under the License is distributed on an "AS IS" - basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See - the License for the specific language governing rights and limitations - under the License. - - </legalnotice> - - <title>Includes</title> - <prepared>Arndt Jonasson</prepared> - <docno>1</docno> - <date>99-01-25</date> - <rev>PA1</rev> - <file>include.sgml</file> - </header> - <p>There are two directives which can be used in Erlang source - files to cause the compiler to temporarily read input from another - source. They are typically used to provide macro definitions and - record definitions from header files. It is recommended to use the - file name extension <c>".hrl"</c> for files which are meant to be - included (the 'h' can be read as "header").</p> - <p>When locating header files a list of directory names, the - compiler include path, is used. In short the list contains the current - working directory of the file server, the base name of the compiled - file, and the directories given by the include option, in that order. - See <c>erlc(1)</c> and <c>compile(3)</c> for the details of the - compiler include path.</p> - - <section> - <title>The -include Directive</title> - <p>The first action taken by the <c>-include</c> directive is to - check if the format of the first path component of the specified - filename is <c>$VAR</c>, for some string <c>VAR</c>. If that is the - case, the value of the environment variable <c>VAR</c> as returned by - <c>os:getenv(VAR)</c> is substituted for the first path component. If - <c>os:getenv/1</c> returns <c>false</c>, the first path component is - left as is. If the filename is absolute (possibly after variable - substitution), the header file with that name is included. Otherwise, - the specified header file is searched for in the directories in the - compiler include path, starting with the first directory in the list. - The first file found while traversing the list is included. Examples:</p> - <code type="none"> - -include("my_records.hrl"). - -include("incdir/more_records.hrl"). - -include("/home/users/proj/recs.hrl"). - -include("$PROJ_ROOT/app1/defs.hrl"). </code> - </section> - - <section> - <title>The -include_lib Directive</title> - <p>The <c>-include_lib</c> directive first tries to find the - specified header file using the procedure employed for the - <c>-include</c> directive. If no header file can be found by searching - the compiler include path, the first path component of the specified - filename (possibly after variable substitution) is regarded as the - name of an application, and the directory of the current version of - the application is searched. Example:</p> - <code type="none"> - -include_lib("mnesia/include/mnemosyne.hrl"). </code> - <p>The compiler is instructed to look for the directory where the - current version of the <c>mnesia</c> application is installed, that is - <c>code:lib_dir(mnesia)</c>, and then search the subdirectory - <c>include</c> for the file <c>mnemosyne.hrl</c>.</p> - </section> -</chapter> - |