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Acknowledgements

Redistribution and use in source (original document form) and 'compiled' forms (converted to PDF, epub, HTML and other formats) with or without modification, are permitted provided that the following conditions are met:

1. Redistributions of source code (original document form) must retain the above copyright notice, this list of conditions and the following disclaimer as the first lines of this file unmodified.

2. Redistributions in compiled form (transformed to other DTDs, converted to PDF, epub, HTML and other formats) must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.

THIS DOCUMENTATION IS PROVIDED BY TIANOCORE PROJECT "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL TIANOCORE PROJECT BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS DOCUMENTATION, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Copyright (c) 2007-2017, Intel Corporation. All rights reserved.

Revision History

Revision	Revision History	Date
1.0	Initial release.	December 2007
1.1	Updated based on errata	August 2008
1.2	Updated based on enhancement requests	June 2009
1.21	Updated based on errata and for enhancement requests	January 2010
	Standardized the format for common content.
	Added support for @Keyword Doxygen tag
	Added support for @ModuleType Doxygen tags
	Added support for @ValidList, @DefaultValue and @ValidRange Doxygen tags for PCDs
	Added PKG_UNI_FILE element to [defines] section
1.22	Errata and grammatical editing	April 2010
1.22 w/	Updates:	December 2011
Errata A	Updated to support UEFI version 2.3.1 and updated spec release dates in Introduction
	Clarify UEFI's PI Distribution Package Specification
	Standardize Common data definitions for all specifications
	Grammatical, formatting and spelling changes
	Replaced "should" with wording saying that it is
	"recommended"
	Added EBNF for <Extension>
	Added scoping rules for Macros, clarified MACRO summary
	Added an example of a binary only DEC file
	Removed references to system environment variables in the Macros section
	Specifically state where <MACROVAL> can be used, and where it is prohibited;
	specifically state that MACROVAL entries are expanded where they are used;
	clarify that MACROS are only expanded, not evaluated during initial parsing of the DEC file
	Added table that shows that every part of a path name can be replaced by a MACROVAL
	Clarify that C data arrays must be byte arrays for PCD value fields; prohibit C format and
	Registry Format GUID structures in VOID* PCD value fields
	Update non-zero number is True, only 0 is consideered False
	Prohibit specifying items as architecturally specific and also common
	Changed <RegistryGuid> to <RegistryFormatGUID> in
	3.4
	Defined <GuidValue> as a <CFormatGUID> for this release (need to allow registry format in a future release)
	Update the [Includes], [Guids], [Protocols], [PPIs], [LibraryClasses] and PCD sections to allow an empty section
	Updated the format for <QuotedString>, <CString> and <UnicodeString>
	Update PATH related EBNF
	Add <MacroDefinition> to [Defines], [Includes] and
	[LibraryClasses] sections
	Provide rules in 2.2.6 for how macros can be shared between different subsections
1.22 w/	Updates:	June 2012
Errata B	Added a + after <Express> in the DoxComment definition of PCDs, as more than one expression can be
	specified in the UEFI PI Distribution Package Specification.
	Added text describing the use of <HexDigit> for error numbers as well as how they are scoped.
1.22 w/	Updates:	June 2012
Errata B	Updated UEFI/PI Spec version in chapter 1.3 to include Errata letters.
(cont.)	In Section 3.10 modified the optional error number in
	DoxComment definitions for PCDs from <HexDigit>+ to
	and defined to be of type ;
	also added a "|" after the value to separate the error code from numeric values
	Added AsBuilt entries for Abstract and Description
	Clarified that the file must use the DOS end-of-line character sequence, 0x0D 0x0A
1.22 w/	Updates:	August 2013
Errata C	Updated UEFI/PI Specification version support in chapter 1
	Modified examples to correct previous errors
	Removed errors from text
	Updated examples
	Modified EBNF to prevent using the architectural modifier of common with any other architecture.
	Ensure that wording specifically states that the architecture modifiers are not case sensitive.
	Add description of PCD processing rules in section 3.10
	Allow registry format GUID values in GUIDs, Protocols,
	PPIs sections instead of requiring C format GUID values
	(which will continue to be allowed)
	The error codes are scoped to the TokenSpaceGUID, not to the PCD
	Added reference to the EDK II Build Specification for PCD processing rules.
1.24	Updates;	August 2014
	Change revision number of this specification from 1.22 to
	1.24
	Updated DEC_SPECIFICATION to 0x00010017
	Added additional parameter definitions for clarification of the comment content for PCDs
	Added the PACKAGE_UNI_FILE entry to the [Defines] section
	Added reserved TianoCore user extension, for
	"ExtraFiles"
	Added PCD comment type for # [Error] which is used to map an error code for a given token space to a specific string.
1.24 w/	Updates:	December 2014
Errata A	Changed DEC_SPECIFICATION to 0x00010018 and allow specifying it as a decimal, i.e., 1.24.
	Updated specification dates and added two new specifications in section 1.2
	Removed expression EBNF as it has been replaced by the EDK II Expression Syntax Specification.
1.24 w/	Updates:	March 2015
Errata B	- Update link to the EDK II Specifications, fixed the name of the Multi-String .UNI File Format Specification
1.24 w/	Updates:	August 2015
Errata C	Clarify that #include statements are not permitted in UNI file specified in the PACKAGE_UNI_FILE entry
1.25	Updates:	January 2015
	Specification revision to 1.25
	Revised WORKSPACE wording for updated build system that can handle
	packages located outside of the WORKSPACE directory tree (refer to
	the TianoCore.org EDKII website for additional instructions on setting
	up a development environment).
1.26	Reformat for GitBook	April 2017
	Updated DEC_SPECIFICATION to 0x0001001A or 1.26
	#465 DEC spec: document private definitions
	#482 DEC Spec: add clarification for [Ppis], [Guids], [Protocols], [Includes] Private support
1.27	Update Version to 1.27	Mar 2018
	Add flexible PCD value format into spec
	Add structure PCD definition syntax
	Add clarification that !error statement is not permitted in DEC file
1.28	#1453 Update DEC spec to remove EDK related contents	Mar 2019
1.29	#1952 add HOST_APPLICATION ModuleType	July 2019