documentation: More information about DL_DIR added.

The information surrounding the central download directory was
pretty scant.  Jim Abernathy pointed this out in an email sent to
me.  As a start, I have added quite a bit more information to
the glossary description for DL_DIR.  Part of that added information
is a pointer to the FAQ entry that describes exactly how the
build system gets source files.  Then, in the YP Development Manual
in the section that introduces the build process, I added several
references to various variables that are set in the local.conf
file prior to kicking off the build.

Reported-by: Jim Abernathy <jim.abernathy@intel.com>
(From yocto-docs rev: 4d7835a3bff5bd054301fa9ab6954c11c88dad58)

Signed-off-by: Scott Rifenbark <scott.m.rifenbark@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 10 insertions, 3 deletions

diff --git a/documentation/dev-manual/dev-manual-start.xml b/documentation/dev-manual/dev-manual-start.xml
index 0ed69cf501..6d68a088d0 100644
--- a/documentation/dev-manual/dev-manual-start.xml
+++ b/documentation/dev-manual/dev-manual-start.xml
@@ -240,9 +240,16 @@
                 previous section.</para></listitem>
             <listitem><para>Initialize the build environment by sourcing a build environment 
                 script.</para></listitem>
-            <listitem><para>Optionally ensure the <filename>conf/local.conf</filename> configuration file is set 
-                up how you want it.  
-                This file defines the target machine architecture and other build options.</para></listitem>
+            <listitem><para>Optionally ensure the <filename>/conf/local.conf</filename> configuration file, 
+                which is found in the Yocto Project build directory, is set up how you want it.  
+                This file defines many aspects of the build environment including 
+                the target machine architecture through the 
+                <filename><ulink url='http://www.yoctoproject.org/docs/latest/poky-ref-manual/poky-ref-manual.html#var-MACHINE'>MACHINE</ulink></filename> variable, 
+                the development machine's processor use through the 
+                <filename><ulink url='http://www.yoctoproject.org/docs/latest/poky-ref-manual/poky-ref-manual.html#var-BB_NUMBER_THREADS'>BB_NUMBER_THREADS</ulink></filename> and 
+                <filename><ulink url='http://www.yoctoproject.org/docs/latest/poky-ref-manual/poky-ref-manual.html#var-PARALLEL_MAKE'>PARALLEL_MAKE</ulink></filename> variables, and
+                a centralized tarball download directory through the  
+                <filename><ulink url='http://www.yoctoproject.org/docs/latest/poky-ref-manual/poky-ref-manual.html#var-DL_DIR'>DL_DIR</ulink></filename> variable.</para></listitem>
             <listitem><para>Build the image using the <command>bitbake</command> command.
                 If you want information on BitBake, see the user manual at
                 <ulink url='http://docs.openembedded.org/bitbake/html'></ulink>.</para></listitem>