diff options
Diffstat (limited to 'documentation/ref-manual/ref-variables.xml')
-rw-r--r-- | documentation/ref-manual/ref-variables.xml | 37 |
1 files changed, 25 insertions, 12 deletions
diff --git a/documentation/ref-manual/ref-variables.xml b/documentation/ref-manual/ref-variables.xml index 137a556d92..09eb9b9dfc 100644 --- a/documentation/ref-manual/ref-variables.xml +++ b/documentation/ref-manual/ref-variables.xml | |||
@@ -10701,27 +10701,40 @@ recipes-graphics/xorg-font/font-alias_1.0.3.bb:PR = "${INC_PR}.3" | |||
10701 | <glossdef> | 10701 | <glossdef> |
10702 | <para role="glossdeffirst"> | 10702 | <para role="glossdeffirst"> |
10703 | <!-- <para role="glossdeffirst"><imagedata fileref="figures/define-generic.png" /> --> | 10703 | <!-- <para role="glossdeffirst"><imagedata fileref="figures/define-generic.png" /> --> |
10704 | If multiple recipes provide an item, this variable | 10704 | If multiple recipes provide the same item, this variable |
10705 | determines which recipe should be given preference. | 10705 | determines which recipe is preferred and thus provides |
10706 | You should always suffix the variable with the name of the | 10706 | the item (i.e. the preferred provider). |
10707 | provided item, and you should set it to the | 10707 | You should always suffix this variable with the name of the |
10708 | <link linkend='var-PN'><filename>PN</filename></link> | 10708 | provided item. |
10709 | of the recipe to which you want to give precedence. | 10709 | And, you should define the variable using the preferred |
10710 | Some examples: | 10710 | recipe's name |
10711 | (<link linkend='var-PN'><filename>PN</filename></link>). | ||
10712 | Here is a common example: | ||
10711 | <literallayout class='monospaced'> | 10713 | <literallayout class='monospaced'> |
10712 | PREFERRED_PROVIDER_virtual/kernel ?= "linux-yocto" | 10714 | PREFERRED_PROVIDER_virtual/kernel ?= "linux-yocto" |
10715 | </literallayout> | ||
10716 | In the previous example, multiple recipes are providing | ||
10717 | "virtual/kernel". | ||
10718 | The <filename>PREFERRED_PROVIDER</filename> variable is | ||
10719 | set with the name (<filename>PN</filename>) of the recipe | ||
10720 | you prefer to provide "virtual/kernel". | ||
10721 | </para> | ||
10722 | |||
10723 | <para> | ||
10724 | Following are more examples: | ||
10725 | <literallayout class='monospaced'> | ||
10713 | PREFERRED_PROVIDER_virtual/xserver = "xserver-xf86" | 10726 | PREFERRED_PROVIDER_virtual/xserver = "xserver-xf86" |
10714 | PREFERRED_PROVIDER_virtual/libgl ?= "mesa" | 10727 | PREFERRED_PROVIDER_virtual/libgl ?= "mesa" |
10715 | </literallayout> | 10728 | </literallayout> |
10716 | For more information, see the | 10729 | For more information, see the |
10717 | "<ulink url='&YOCTO_DOCS_CM_URL;#metadata-virtual-providers'>Metadata (Virtual Providers)</ulink>" | 10730 | "<ulink url='&YOCTO_DOCS_DEV_URL;#metadata-virtual-providers'>Using Virtual Providers</ulink>" |
10718 | section in the Yocto Project Concepts Manual. | 10731 | section in the Yocto Project Development Tasks Manual. |
10719 | <note> | 10732 | <note> |
10720 | If you set <filename>PREFERRED_PROVIDER</filename> | 10733 | If you use a <filename>virtual/*</filename> item |
10721 | for a <filename>virtual/*</filename> item, then any | 10734 | with <filename>PREFERRED_PROVIDER</filename>, then any |
10722 | recipe that | 10735 | recipe that |
10723 | <link linkend='var-PROVIDES'><filename>PROVIDES</filename></link> | 10736 | <link linkend='var-PROVIDES'><filename>PROVIDES</filename></link> |
10724 | that item that is not selected by | 10737 | that item but is not selected (defined) by |
10725 | <filename>PREFERRED_PROVIDER</filename> is prevented | 10738 | <filename>PREFERRED_PROVIDER</filename> is prevented |
10726 | from building, which is usually desirable since this | 10739 | from building, which is usually desirable since this |
10727 | mechanism is designed to select between mutually | 10740 | mechanism is designed to select between mutually |