<html><head><title> Porting Hints </title></head><body><h3> Porting Hints </h3> <img align=left src=pic/wingdorothy.gif><a href=http://www.eecis.udel.edu/~mills/pictures.htm>from <i>The Wizard of Oz</i>, L. Frank Baum</a> <p>Porting Dorothy in Oz. <br clear=left><hr> <p>NOTE: The following procedures have been replaced by GNU automake and autoconfigure. This page is to be updated in the next release. <p>Porting to a new machine or operating system ordinarily requires updating the <code>./machines</code> directory and the <code>./compilers</code> directories in order to define the build environment and autoconfigure means. You will probably have to modify the <code>ntp_machines.h</code> file and <code>"l_stdlib.h"</code> files as well. The two most famous trouble spots are the I/O code in <code>./ntpd/ntp_io.c</code> and the clock adjustment code in <code>./ntpd/ntp_unixclock.c</code>. <p>These are the rules so that older bsd systems and the POSIX standard system can coexist together. <ol> <li>If you use <code>select</code> then include <code>"ntp_select.h"</code>. <code>select</code> is not standard, since it is very system dependent as to where it is defined. The logic to include the right system dependent include file is in <code>"ntp_select.h"</code>. <p><li>Always use POSIX definition of strings. Include <code>"ntp_string.h"</code> instead of <code><string.h></code>. <p><li>Always include <code>"ntp_malloc.h"</code> if you use <code>malloc</code>. <p><li>Always include <code>"ntp_io.h"</code> instead of <code><sys/file.h></code> or <code><fnctl.h></code> to get <code>O_*</code> flags. <p><li>Always include <code>"ntp_if.h"</code> instead of <code><net/if.h></code>. <p><li>Always include <code>"ntp_stdlib.h"</code> instead of <code><stdlib.h></code>. <p><li>Define any special defines needed for a system in <code>./include/ntp_machine.h</code> based on system identifier. This file is included by the <code>"ntp_types.h"</code> file and should always be placed first after the <code><></code> defines. <p><li>Define any special library prototypes left over from the system library and include files in the <code>"l_stdlib.h"</code> file. This file is included by the <code>"ntp_stdlib.h"</code> file and should ordinarily be placed last in the includes list. <p><li>Don't define a include file by the same name as a system include file. </ol> <p><code>"l_stdlib.h"</code> can contain any extra definitions that are needed so that <code>gcc</code> will shut up. They should be controlled by a system identifier and there should be a separate section for each system. Really this will make it easier to maintain. <p>See <code>include/ntp_machines.h</code> for the various compile time options. <p>When you are satisfied the port works and that other ports are not adversely affected, please send <a href="patches.htm">patches</a> for the system files you have changed, as well as any documentation that should be updated, including the advice herein. <p>Good luck. <hr><a href=index.htm><img align=left src=pic/home.gif></a><address><a href=mailto:mills@udel.edu> David L. Mills <mills@udel.edu></a> </address></a></body></html>