<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN">
<HTML
><HEAD
><TITLE
>Symbols</TITLE
><META
NAME="GENERATOR"
CONTENT="Modular DocBook HTML Stylesheet Version 1.7"><LINK
REL="HOME"
TITLE="Unreliable Guide To Hacking The Linux Kernel"
HREF="book1.html"><LINK
REL="PREVIOUS"
TITLE="Atomic Operations"
HREF="c359.html"><LINK
REL="NEXT"
TITLE="EXPORT_NO_SYMBOLS
include/linux/module.h"
HREF="x396.html"></HEAD
><BODY
CLASS="CHAPTER"
BGCOLOR="#FFFFFF"
TEXT="#000000"
LINK="#0000FF"
VLINK="#840084"
ALINK="#0000FF"
><DIV
CLASS="NAVHEADER"
><TABLE
SUMMARY="Header navigation table"
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
><TR
><TH
COLSPAN="3"
ALIGN="center"
>Unreliable Guide To Hacking The Linux Kernel</TH
></TR
><TR
><TD
WIDTH="10%"
ALIGN="left"
VALIGN="bottom"
><A
HREF="c359.html"
ACCESSKEY="P"
><<< Previous</A
></TD
><TD
WIDTH="80%"
ALIGN="center"
VALIGN="bottom"
></TD
><TD
WIDTH="10%"
ALIGN="right"
VALIGN="bottom"
><A
HREF="x396.html"
ACCESSKEY="N"
>Next >>></A
></TD
></TR
></TABLE
><HR
ALIGN="LEFT"
WIDTH="100%"></DIV
><DIV
CLASS="CHAPTER"
><H1
><A
NAME="SYMBOLS"
></A
>Symbols</H1
><P
> Within the kernel proper, the normal linking rules apply
(ie. unless a symbol is declared to be file scope with the
<SPAN
CLASS="TYPE"
>static</SPAN
> keyword, it can be used anywhere in the
kernel). However, for modules, a special exported symbol table is
kept which limits the entry points to the kernel proper. Modules
can also export symbols.
</P
><DIV
CLASS="SECT1"
><H1
CLASS="SECT1"
><A
NAME="SYM-EXPORTSYMBOLS"
></A
><TT
CLASS="FUNCTION"
>EXPORT_SYMBOL()</TT
>
<TT
CLASS="FILENAME"
>include/linux/module.h</TT
></H1
><P
> This is the classic method of exporting a symbol, and it works
for both modules and non-modules. In the kernel all these
declarations are often bundled into a single file to help
genksyms (which searches source files for these declarations).
See the comment on genksyms and Makefiles below.
</P
></DIV
></DIV
><DIV
CLASS="NAVFOOTER"
><HR
ALIGN="LEFT"
WIDTH="100%"><TABLE
SUMMARY="Footer navigation table"
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
><A
HREF="c359.html"
ACCESSKEY="P"
><<< Previous</A
></TD
><TD
WIDTH="34%"
ALIGN="center"
VALIGN="top"
><A
HREF="book1.html"
ACCESSKEY="H"
>Home</A
></TD
><TD
WIDTH="33%"
ALIGN="right"
VALIGN="top"
><A
HREF="x396.html"
ACCESSKEY="N"
>Next >>></A
></TD
></TR
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
>Atomic Operations</TD
><TD
WIDTH="34%"
ALIGN="center"
VALIGN="top"
> </TD
><TD
WIDTH="33%"
ALIGN="right"
VALIGN="top"
><SPAN
CLASS="SYMBOL"
>EXPORT_NO_SYMBOLS</SPAN
>
<TT
CLASS="FILENAME"
>include/linux/module.h</TT
></TD
></TR
></TABLE
></DIV
></BODY
></HTML
>
