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Issue 10804012: Add native Windows binary for gperf. (Closed) Base URL: svn://chrome-svn/chrome/trunk/deps/third_party/
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Index: gperf/src/gperf/3.0.1/gperf-3.0.1-src/doc/gperf.html
===================================================================
--- gperf/src/gperf/3.0.1/gperf-3.0.1-src/doc/gperf.html (revision 0)
+++ gperf/src/gperf/3.0.1/gperf-3.0.1-src/doc/gperf.html (revision 0)
@@ -0,0 +1,2069 @@
+<HTML>
+<HEAD>
+<!-- Created by texi2html 1.56k from gperf.texi on 12 June 2003 -->
+
+<TITLE>Perfect Hash Function Generator</TITLE>
+</HEAD>
+<BODY>
+<H1>User's Guide to <CODE>gperf</CODE> 3.0.1</H1>
+<H2>The GNU Perfect Hash Function Generator</H2>
+<H2>Edition 3.0.1, 12 June 2003</H2>
+<ADDRESS>Douglas C. Schmidt</ADDRESS>
+<ADDRESS>Bruno Haible</ADDRESS>
+<P>
+<P><HR><P>
+<H1>Table of Contents</H1>
+<UL>
+<LI><A NAME="TOC1" HREF="gperf.html#SEC1">GNU GENERAL PUBLIC LICENSE</A>
+<UL>
+<LI><A NAME="TOC2" HREF="gperf.html#SEC2">Preamble</A>
+<LI><A NAME="TOC3" HREF="gperf.html#SEC3">How to Apply These Terms to Your New Programs</A>
+</UL>
+<LI><A NAME="TOC4" HREF="gperf.html#SEC4">Contributors to GNU <CODE>gperf</CODE> Utility</A>
+<LI><A NAME="TOC5" HREF="gperf.html#SEC5">1. Introduction</A>
+<LI><A NAME="TOC6" HREF="gperf.html#SEC6">2. Static search structures and GNU <CODE>gperf</CODE></A>
+<LI><A NAME="TOC7" HREF="gperf.html#SEC7">3. High-Level Description of GNU <CODE>gperf</CODE></A>
+<UL>
+<LI><A NAME="TOC8" HREF="gperf.html#SEC8">3.1 Input Format to <CODE>gperf</CODE></A>
+<UL>
+<LI><A NAME="TOC9" HREF="gperf.html#SEC9">3.1.1 Declarations</A>
+<UL>
+<LI><A NAME="TOC10" HREF="gperf.html#SEC10">3.1.1.1 User-supplied <CODE>struct</CODE></A>
+<LI><A NAME="TOC11" HREF="gperf.html#SEC11">3.1.1.2 Gperf Declarations</A>
+<LI><A NAME="TOC12" HREF="gperf.html#SEC12">3.1.1.3 C Code Inclusion</A>
+</UL>
+<LI><A NAME="TOC13" HREF="gperf.html#SEC13">3.1.2 Format for Keyword Entries</A>
+<LI><A NAME="TOC14" HREF="gperf.html#SEC14">3.1.3 Including Additional C Functions</A>
+<LI><A NAME="TOC15" HREF="gperf.html#SEC15">3.1.4 Where to place directives for GNU <CODE>indent</CODE>.</A>
+</UL>
+<LI><A NAME="TOC16" HREF="gperf.html#SEC16">3.2 Output Format for Generated C Code with <CODE>gperf</CODE></A>
+<LI><A NAME="TOC17" HREF="gperf.html#SEC17">3.3 Use of NUL bytes</A>
+</UL>
+<LI><A NAME="TOC18" HREF="gperf.html#SEC18">4. Invoking <CODE>gperf</CODE></A>
+<UL>
+<LI><A NAME="TOC19" HREF="gperf.html#SEC19">4.1 Specifying the Location of the Output File</A>
+<LI><A NAME="TOC20" HREF="gperf.html#SEC20">4.2 Options that affect Interpretation of the Input File</A>
+<LI><A NAME="TOC21" HREF="gperf.html#SEC21">4.3 Options to specify the Language for the Output Code</A>
+<LI><A NAME="TOC22" HREF="gperf.html#SEC22">4.4 Options for fine tuning Details in the Output Code</A>
+<LI><A NAME="TOC23" HREF="gperf.html#SEC23">4.5 Options for changing the Algorithms employed by <CODE>gperf</CODE></A>
+<LI><A NAME="TOC24" HREF="gperf.html#SEC24">4.6 Informative Output</A>
+</UL>
+<LI><A NAME="TOC25" HREF="gperf.html#SEC25">5. Known Bugs and Limitations with <CODE>gperf</CODE></A>
+<LI><A NAME="TOC26" HREF="gperf.html#SEC26">6. Things Still Left to Do</A>
+<LI><A NAME="TOC27" HREF="gperf.html#SEC27">7. Bibliography</A>
+<LI><A NAME="TOC28" HREF="gperf.html#SEC28">Concept Index</A>
+</UL>
+<P><HR><P>
+
+
+<H1><A NAME="SEC1" HREF="gperf.html#TOC1">GNU GENERAL PUBLIC LICENSE</A></H1>
+
+<P>
+Version 2, June 1991
+
+
+
+<PRE>
+Copyright (C) 1989, 1991 Free Software Foundation, Inc.,
+59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
+
+Everyone is permitted to copy and distribute verbatim copies
+of this license document, but changing it is not allowed.
+</PRE>
+
+
+
+<H2><A NAME="SEC2" HREF="gperf.html#TOC2">Preamble</A></H2>
+
+<P>
+ The licenses for most software are designed to take away your
+freedom to share and change it. By contrast, the GNU General Public
+License is intended to guarantee your freedom to share and change free
+software--to make sure the software is free for all its users. This
+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it. (Some other Free Software Foundation software is covered by
+the GNU Library General Public License instead.) You can apply it to
+your programs, too.
+
+
+<P>
+ When we speak of free software, we are referring to freedom, not
+price. Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+this service if you wish), that you receive source code or can get it
+if you want it, that you can change the software or use pieces of it
+in new free programs; and that you know you can do these things.
+
+
+<P>
+ To protect your rights, we need to make restrictions that forbid
+anyone to deny you these rights or to ask you to surrender the rights.
+These restrictions translate to certain responsibilities for you if you
+distribute copies of the software, or if you modify it.
+
+
+<P>
+ For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must give the recipients all the rights that
+you have. You must make sure that they, too, receive or can get the
+source code. And you must show them these terms so they know their
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+
+
+<P>
+ We protect your rights with two steps: (1) copyright the software, and
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+
+
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+that everyone understands that there is no warranty for this free
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+
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+ Finally, any free program is threatened constantly by software
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+
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+
+
+<P>
+TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+
+
+<OL>
+<LI>
+
+This License applies to any program or other work which contains
+a notice placed by the copyright holder saying it may be distributed
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+language. (Hereinafter, translation is included without limitation in
+the term "modification".) Each licensee is addressed as "you".
+
+Activities other than copying, distribution and modification are not
+covered by this License; they are outside its scope. The act of
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+Whether that is true depends on what the Program does.
+
+<LI>
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+You may copy and distribute verbatim copies of the Program's
+source code as you receive it, in any medium, provided that you
+conspicuously and appropriately publish on each copy an appropriate
+copyright notice and disclaimer of warranty; keep intact all the
+notices that refer to this License and to the absence of any warranty;
+and give any other recipients of the Program a copy of this License
+along with the Program.
+
+You may charge a fee for the physical act of transferring a copy, and
+you may at your option offer warranty protection in exchange for a fee.
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+<LI>
+
+You may modify your copy or copies of the Program or any portion
+of it, thus forming a work based on the Program, and copy and
+distribute such modifications or work under the terms of Section 1
+above, provided that you also meet all of these conditions:
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+
+<OL>
+<LI>
+
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+stating that you changed the files and the date of any change.
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+
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+If the modified program normally reads commands interactively
+when run, you must cause it, when started running for such
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+</OL>
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+These requirements apply to the modified work as a whole. If
+identifiable sections of that work are not derived from the Program,
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+on the Program, the distribution of the whole must be on the terms of
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+with the Program (or with a work based on the Program) on a volume of
+a storage or distribution medium does not bring the other work under
+the scope of this License.
+
+<LI>
+
+You may copy and distribute the Program (or a work based on it,
+under Section 2) in object code or executable form under the terms of
+Sections 1 and 2 above provided that you also do one of the following:
+
+
+<OL>
+<LI>
+
+Accompany it with the complete corresponding machine-readable
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+
+<LI>
+
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+years, to give any third party, for a charge no more than your
+cost of physically performing source distribution, a complete
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+customarily used for software interchange; or,
+
+<LI>
+
+Accompany it with the information you received as to the offer
+to distribute corresponding source code. (This alternative is
+allowed only for noncommercial distribution and only if you
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+</OL>
+
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+
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+compelled to copy the source along with the object code.
+
+<LI>
+
+You may not copy, modify, sublicense, or distribute the Program
+except as expressly provided under this License. Any attempt
+otherwise to copy, modify, sublicense or distribute the Program is
+void, and will automatically terminate your rights under this License.
+However, parties who have received copies, or rights, from you under
+this License will not have their licenses terminated so long as such
+parties remain in full compliance.
+
+<LI>
+
+You are not required to accept this License, since you have not
+signed it. However, nothing else grants you permission to modify or
+distribute the Program or its derivative works. These actions are
+prohibited by law if you do not accept this License. Therefore, by
+modifying or distributing the Program (or any work based on the
+Program), you indicate your acceptance of this License to do so, and
+all its terms and conditions for copying, distributing or modifying
+the Program or works based on it.
+
+<LI>
+
+Each time you redistribute the Program (or any work based on the
+Program), the recipient automatically receives a license from the
+original licensor to copy, distribute or modify the Program subject to
+these terms and conditions. You may not impose any further
+restrictions on the recipients' exercise of the rights granted herein.
+You are not responsible for enforcing compliance by third parties to
+this License.
+
+<LI>
+
+If, as a consequence of a court judgment or allegation of patent
+infringement or for any other reason (not limited to patent issues),
+conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License. If you cannot
+distribute so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you
+may not distribute the Program at all. For example, if a patent
+license would not permit royalty-free redistribution of the Program by
+all those who receive copies directly or indirectly through you, then
+the only way you could satisfy both it and this License would be to
+refrain entirely from distribution of the Program.
+
+If any portion of this section is held invalid or unenforceable under
+any particular circumstance, the balance of the section is intended to
+apply and the section as a whole is intended to apply in other
+circumstances.
+
+It is not the purpose of this section to induce you to infringe any
+patents or other property right claims or to contest validity of any
+such claims; this section has the sole purpose of protecting the
+integrity of the free software distribution system, which is
+implemented by public license practices. Many people have made
+generous contributions to the wide range of software distributed
+through that system in reliance on consistent application of that
+system; it is up to the author/donor to decide if he or she is willing
+to distribute software through any other system and a licensee cannot
+impose that choice.
+
+This section is intended to make thoroughly clear what is believed to
+be a consequence of the rest of this License.
+
+<LI>
+
+If the distribution and/or use of the Program is restricted in
+certain countries either by patents or by copyrighted interfaces, the
+original copyright holder who places the Program under this License
+may add an explicit geographical distribution limitation excluding
+those countries, so that distribution is permitted only in or among
+countries not thus excluded. In such case, this License incorporates
+the limitation as if written in the body of this License.
+
+<LI>
+
+The Free Software Foundation may publish revised and/or new versions
+of the General Public License from time to time. Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+Each version is given a distinguishing version number. If the Program
+specifies a version number of this License which applies to it and "any
+later version", you have the option of following the terms and conditions
+either of that version or of any later version published by the Free
+Software Foundation. If the Program does not specify a version number of
+this License, you may choose any version ever published by the Free Software
+Foundation.
+
+<LI>
+
+If you wish to incorporate parts of the Program into other free
+programs whose distribution conditions are different, write to the author
+to ask for permission. For software which is copyrighted by the Free
+Software Foundation, write to the Free Software Foundation; we sometimes
+make exceptions for this. Our decision will be guided by the two goals
+of preserving the free status of all derivatives of our free software and
+of promoting the sharing and reuse of software generally.
+
+NO WARRANTY
+
+<LI>
+
+BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
+FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN
+OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
+PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
+OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS
+TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE
+PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
+REPAIR OR CORRECTION.
+
+<LI>
+
+IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
+REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
+INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
+OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
+TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
+YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
+PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGES.
+</OL>
+
+<P>
+END OF TERMS AND CONDITIONS
+
+
+
+
+<H2><A NAME="SEC3" HREF="gperf.html#TOC3">How to Apply These Terms to Your New Programs</A></H2>
+
+<P>
+ If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+
+<P>
+ To do so, attach the following notices to the program. It is safest
+to attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+
+
+<PRE>
+<VAR>one line to give the program's name and an idea of what it does.</VAR>
+Copyright (C) <VAR>year</VAR> <VAR>name of author</VAR>
+
+This program is free software; you can redistribute it and/or
+modify it under the terms of the GNU General Public License
+as published by the Free Software Foundation; either version 2
+of the License, or (at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
+</PRE>
+
+<P>
+Also add information on how to contact you by electronic and paper mail.
+
+
+<P>
+If the program is interactive, make it output a short notice like this
+when it starts in an interactive mode:
+
+
+
+<PRE>
+Gnomovision version 69, Copyright (C) <VAR>year</VAR> <VAR>name of author</VAR>
+Gnomovision comes with ABSOLUTELY NO WARRANTY; for details
+type `show w'. This is free software, and you are welcome
+to redistribute it under certain conditions; type `show c'
+for details.
+</PRE>
+
+<P>
+The hypothetical commands <SAMP>`show w'</SAMP> and <SAMP>`show c'</SAMP> should show
+the appropriate parts of the General Public License. Of course, the
+commands you use may be called something other than <SAMP>`show w'</SAMP> and
+<SAMP>`show c'</SAMP>; they could even be mouse-clicks or menu items--whatever
+suits your program.
+
+
+<P>
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the program, if
+necessary. Here is a sample; alter the names:
+
+
+
+<PRE>
+Yoyodyne, Inc., hereby disclaims all copyright
+interest in the program `Gnomovision'
+(which makes passes at compilers) written
+by James Hacker.
+
+<VAR>signature of Ty Coon</VAR>, 1 April 1989
+Ty Coon, President of Vice
+</PRE>
+
+<P>
+This General Public License does not permit incorporating your program into
+proprietary programs. If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library. If this is what you want to do, use the GNU Library General
+Public License instead of this License.
+
+
+
+
+<H1><A NAME="SEC4" HREF="gperf.html#TOC4">Contributors to GNU <CODE>gperf</CODE> Utility</A></H1>
+
+
+<UL>
+<LI>
+
+<A NAME="IDX1"></A>
+The GNU <CODE>gperf</CODE> perfect hash function generator utility was
+written in GNU C++ by Douglas C. Schmidt. The general
+idea for the perfect hash function generator was inspired by Keith
+Bostic's algorithm written in C, and distributed to net.sources around
+1984. The current program is a heavily modified, enhanced, and extended
+implementation of Keith's basic idea, created at the University of
+California, Irvine. Bugs, patches, and suggestions should be reported
+to <CODE>&#60;bug-gnu-gperf@gnu.org&#62;</CODE>.
+
+<LI>
+
+Special thanks is extended to Michael Tiemann and Doug Lea, for
+providing a useful compiler, and for giving me a forum to exhibit my
+creation.
+
+In addition, Adam de Boor and Nels Olson provided many tips and insights
+that greatly helped improve the quality and functionality of <CODE>gperf</CODE>.
+
+<LI>
+
+Bruno Haible enhanced and optimized the search algorithm. He also rewrote
+the input routines and the output routines for better reliability, and
+added a testsuite.
+</UL>
+
+
+
+<H1><A NAME="SEC5" HREF="gperf.html#TOC5">1. Introduction</A></H1>
+
+<P>
+<CODE>gperf</CODE> is a perfect hash function generator written in C++. It
+transforms an <VAR>n</VAR> element user-specified keyword set <VAR>W</VAR> into a
+perfect hash function <VAR>F</VAR>. <VAR>F</VAR> uniquely maps keywords in
+<VAR>W</VAR> onto the range 0..<VAR>k</VAR>, where <VAR>k</VAR> &#62;= <VAR>n-1</VAR>. If <VAR>k</VAR>
+= <VAR>n-1</VAR> then <VAR>F</VAR> is a <EM>minimal</EM> perfect hash function.
+<CODE>gperf</CODE> generates a 0..<VAR>k</VAR> element static lookup table and a
+pair of C functions. These functions determine whether a given
+character string <VAR>s</VAR> occurs in <VAR>W</VAR>, using at most one probe into
+the lookup table.
+
+
+<P>
+<CODE>gperf</CODE> currently generates the reserved keyword recognizer for
+lexical analyzers in several production and research compilers and
+language processing tools, including GNU C, GNU C++, GNU Java, GNU Pascal,
+GNU Modula 3, and GNU indent. Complete C++ source code for <CODE>gperf</CODE> is
+available from <CODE>http://ftp.gnu.org/pub/gnu/gperf/</CODE>.
+A paper describing <CODE>gperf</CODE>'s design and implementation in greater
+detail is available in the Second USENIX C++ Conference proceedings
+or from <CODE>http://www.cs.wustl.edu/~schmidt/resume.html</CODE>.
+
+
+
+
+<H1><A NAME="SEC6" HREF="gperf.html#TOC6">2. Static search structures and GNU <CODE>gperf</CODE></A></H1>
+<P>
+<A NAME="IDX2"></A>
+
+
+<P>
+A <EM>static search structure</EM> is an Abstract Data Type with certain
+fundamental operations, e.g., <EM>initialize</EM>, <EM>insert</EM>,
+and <EM>retrieve</EM>. Conceptually, all insertions occur before any
+retrievals. In practice, <CODE>gperf</CODE> generates a <EM>static</EM> array
+containing search set keywords and any associated attributes specified
+by the user. Thus, there is essentially no execution-time cost for the
+insertions. It is a useful data structure for representing <EM>static
+search sets</EM>. Static search sets occur frequently in software system
+applications. Typical static search sets include compiler reserved
+words, assembler instruction opcodes, and built-in shell interpreter
+commands. Search set members, called <EM>keywords</EM>, are inserted into
+the structure only once, usually during program initialization, and are
+not generally modified at run-time.
+
+
+<P>
+Numerous static search structure implementations exist, e.g.,
+arrays, linked lists, binary search trees, digital search tries, and
+hash tables. Different approaches offer trade-offs between space
+utilization and search time efficiency. For example, an <VAR>n</VAR> element
+sorted array is space efficient, though the average-case time
+complexity for retrieval operations using binary search is
+proportional to log <VAR>n</VAR>. Conversely, hash table implementations
+often locate a table entry in constant time, but typically impose
+additional memory overhead and exhibit poor worst case performance.
+
+
+<P>
+<A NAME="IDX3"></A>
+<EM>Minimal perfect hash functions</EM> provide an optimal solution for a
+particular class of static search sets. A minimal perfect hash
+function is defined by two properties:
+
+
+
+<UL>
+<LI>
+
+It allows keyword recognition in a static search set using at most
+<EM>one</EM> probe into the hash table. This represents the "perfect"
+property.
+<LI>
+
+The actual memory allocated to store the keywords is precisely large
+enough for the keyword set, and <EM>no larger</EM>. This is the
+"minimal" property.
+</UL>
+
+<P>
+For most applications it is far easier to generate <EM>perfect</EM> hash
+functions than <EM>minimal perfect</EM> hash functions. Moreover,
+non-minimal perfect hash functions frequently execute faster than
+minimal ones in practice. This phenomena occurs since searching a
+sparse keyword table increases the probability of locating a "null"
+entry, thereby reducing string comparisons. <CODE>gperf</CODE>'s default
+behavior generates <EM>near-minimal</EM> perfect hash functions for
+keyword sets. However, <CODE>gperf</CODE> provides many options that permit
+user control over the degree of minimality and perfection.
+
+
+<P>
+Static search sets often exhibit relative stability over time. For
+example, Ada's 63 reserved words have remained constant for nearly a
+decade. It is therefore frequently worthwhile to expend concerted
+effort building an optimal search structure <EM>once</EM>, if it
+subsequently receives heavy use multiple times. <CODE>gperf</CODE> removes
+the drudgery associated with constructing time- and space-efficient
+search structures by hand. It has proven a useful and practical tool
+for serious programming projects. Output from <CODE>gperf</CODE> is currently
+used in several production and research compilers, including GNU C, GNU
+C++, GNU Java, GNU Pascal, and GNU Modula 3. The latter two compilers are
+not yet part of the official GNU distribution. Each compiler utilizes
+<CODE>gperf</CODE> to automatically generate static search structures that
+efficiently identify their respective reserved keywords.
+
+
+
+
+<H1><A NAME="SEC7" HREF="gperf.html#TOC7">3. High-Level Description of GNU <CODE>gperf</CODE></A></H1>
+
+<P>
+The perfect hash function generator <CODE>gperf</CODE> reads a set of
+"keywords" from an input file (or from the standard input by
+default). It attempts to derive a perfect hashing function that
+recognizes a member of the <EM>static keyword set</EM> with at most a
+single probe into the lookup table. If <CODE>gperf</CODE> succeeds in
+generating such a function it produces a pair of C source code routines
+that perform hashing and table lookup recognition. All generated C code
+is directed to the standard output. Command-line options described
+below allow you to modify the input and output format to <CODE>gperf</CODE>.
+
+
+<P>
+By default, <CODE>gperf</CODE> attempts to produce time-efficient code, with
+less emphasis on efficient space utilization. However, several options
+exist that permit trading-off execution time for storage space and vice
+versa. In particular, expanding the generated table size produces a
+sparse search structure, generally yielding faster searches.
+Conversely, you can direct <CODE>gperf</CODE> to utilize a C <CODE>switch</CODE>
+statement scheme that minimizes data space storage size. Furthermore,
+using a C <CODE>switch</CODE> may actually speed up the keyword retrieval time
+somewhat. Actual results depend on your C compiler, of course.
+
+
+<P>
+In general, <CODE>gperf</CODE> assigns values to the bytes it is using
+for hashing until some set of values gives each keyword a unique value.
+A helpful heuristic is that the larger the hash value range, the easier
+it is for <CODE>gperf</CODE> to find and generate a perfect hash function.
+Experimentation is the key to getting the most from <CODE>gperf</CODE>.
+
+
+
+
+<H2><A NAME="SEC8" HREF="gperf.html#TOC8">3.1 Input Format to <CODE>gperf</CODE></A></H2>
+<P>
+<A NAME="IDX4"></A>
+<A NAME="IDX5"></A>
+<A NAME="IDX6"></A>
+<A NAME="IDX7"></A>
+You can control the input file format by varying certain command-line
+arguments, in particular the <SAMP>`-t'</SAMP> option. The input's appearance
+is similar to GNU utilities <CODE>flex</CODE> and <CODE>bison</CODE> (or UNIX
+utilities <CODE>lex</CODE> and <CODE>yacc</CODE>). Here's an outline of the general
+format:
+
+
+
+<PRE>
+declarations
+%%
+keywords
+%%
+functions
+</PRE>
+
+<P>
+<EM>Unlike</EM> <CODE>flex</CODE> or <CODE>bison</CODE>, the declarations section and
+the functions section are optional. The following sections describe the
+input format for each section.
+
+
+<P>
+It is possible to omit the declaration section entirely, if the <SAMP>`-t'</SAMP>
+option is not given. In this case the input file begins directly with the
+first keyword line, e.g.:
+
+
+
+<PRE>
+january
+february
+march
+april
+...
+</PRE>
+
+
+
+<H3><A NAME="SEC9" HREF="gperf.html#TOC9">3.1.1 Declarations</A></H3>
+
+<P>
+The keyword input file optionally contains a section for including
+arbitrary C declarations and definitions, <CODE>gperf</CODE> declarations that
+act like command-line options, as well as for providing a user-supplied
+<CODE>struct</CODE>.
+
+
+
+
+<H4><A NAME="SEC10" HREF="gperf.html#TOC10">3.1.1.1 User-supplied <CODE>struct</CODE></A></H4>
+
+<P>
+If the <SAMP>`-t'</SAMP> option (or, equivalently, the <SAMP>`%struct-type'</SAMP> declaration)
+<EM>is</EM> enabled, you <EM>must</EM> provide a C <CODE>struct</CODE> as the last
+component in the declaration section from the input file. The first
+field in this struct must be of type <CODE>char *</CODE> or <CODE>const char *</CODE>
+if the <SAMP>`-P'</SAMP> option is not given, or of type <CODE>int</CODE> if the option
+<SAMP>`-P'</SAMP> (or, equivalently, the <SAMP>`%pic'</SAMP> declaration) is enabled.
+This first field must be called <SAMP>`name'</SAMP>, although it is possible to modify
+its name with the <SAMP>`-K'</SAMP> option (or, equivalently, the
+<SAMP>`%define slot-name'</SAMP> declaration) described below.
+
+
+<P>
+Here is a simple example, using months of the year and their attributes as
+input:
+
+
+
+<PRE>
+struct month { char *name; int number; int days; int leap_days; };
+%%
+january, 1, 31, 31
+february, 2, 28, 29
+march, 3, 31, 31
+april, 4, 30, 30
+may, 5, 31, 31
+june, 6, 30, 30
+july, 7, 31, 31
+august, 8, 31, 31
+september, 9, 30, 30
+october, 10, 31, 31
+november, 11, 30, 30
+december, 12, 31, 31
+</PRE>
+
+<P>
+<A NAME="IDX8"></A>
+Separating the <CODE>struct</CODE> declaration from the list of keywords and
+other fields are a pair of consecutive percent signs, <SAMP>`%%'</SAMP>,
+appearing left justified in the first column, as in the UNIX utility
+<CODE>lex</CODE>.
+
+
+<P>
+If the <CODE>struct</CODE> has already been declared in an include file, it can
+be mentioned in an abbreviated form, like this:
+
+
+
+<PRE>
+struct month;
+%%
+january, 1, 31, 31
+...
+</PRE>
+
+
+
+<H4><A NAME="SEC11" HREF="gperf.html#TOC11">3.1.1.2 Gperf Declarations</A></H4>
+
+<P>
+The declaration section can contain <CODE>gperf</CODE> declarations. They
+influence the way <CODE>gperf</CODE> works, like command line options do.
+In fact, every such declaration is equivalent to a command line option.
+There are three forms of declarations:
+
+
+
+<OL>
+<LI>
+
+Declarations without argument, like <SAMP>`%compare-lengths'</SAMP>.
+
+<LI>
+
+Declarations with an argument, like <SAMP>`%switch=<VAR>count</VAR>'</SAMP>.
+
+<LI>
+
+Declarations of names of entities in the output file, like
+<SAMP>`%define lookup-function-name <VAR>name</VAR>'</SAMP>.
+</OL>
+
+<P>
+When a declaration is given both in the input file and as a command line
+option, the command-line option's value prevails.
+
+
+<P>
+The following <CODE>gperf</CODE> declarations are available.
+
+
+<DL COMPACT>
+
+<DT><SAMP>`%delimiters=<VAR>delimiter-list</VAR>'</SAMP>
+<DD>
+<A NAME="IDX9"></A>
+Allows you to provide a string containing delimiters used to
+separate keywords from their attributes. The default is ",". This
+option is essential if you want to use keywords that have embedded
+commas or newlines.
+
+<DT><SAMP>`%struct-type'</SAMP>
+<DD>
+<A NAME="IDX10"></A>
+Allows you to include a <CODE>struct</CODE> type declaration for generated
+code; see above for an example.
+
+<DT><SAMP>`%ignore-case'</SAMP>
+<DD>
+<A NAME="IDX11"></A>
+Consider upper and lower case ASCII characters as equivalent. The string
+comparison will use a case insignificant character comparison. Note that
+locale dependent case mappings are ignored.
+
+<DT><SAMP>`%language=<VAR>language-name</VAR>'</SAMP>
+<DD>
+<A NAME="IDX12"></A>
+Instructs <CODE>gperf</CODE> to generate code in the language specified by the
+option's argument. Languages handled are currently:
+
+<DL COMPACT>
+
+<DT><SAMP>`KR-C'</SAMP>
+<DD>
+Old-style K&#38;R C. This language is understood by old-style C compilers and
+ANSI C compilers, but ANSI C compilers may flag warnings (or even errors)
+because of lacking <SAMP>`const'</SAMP>.
+
+<DT><SAMP>`C'</SAMP>
+<DD>
+Common C. This language is understood by ANSI C compilers, and also by
+old-style C compilers, provided that you <CODE>#define const</CODE> to empty
+for compilers which don't know about this keyword.
+
+<DT><SAMP>`ANSI-C'</SAMP>
+<DD>
+ANSI C. This language is understood by ANSI C compilers and C++ compilers.
+
+<DT><SAMP>`C++'</SAMP>
+<DD>
+C++. This language is understood by C++ compilers.
+</DL>
+
+The default is C.
+
+<DT><SAMP>`%define slot-name <VAR>name</VAR>'</SAMP>
+<DD>
+<A NAME="IDX13"></A>
+This declaration is only useful when option <SAMP>`-t'</SAMP> (or, equivalently, the
+<SAMP>`%struct-type'</SAMP> declaration) has been given.
+By default, the program assumes the structure component identifier for
+the keyword is <SAMP>`name'</SAMP>. This option allows an arbitrary choice of
+identifier for this component, although it still must occur as the first
+field in your supplied <CODE>struct</CODE>.
+
+<DT><SAMP>`%define initializer-suffix <VAR>initializers</VAR>'</SAMP>
+<DD>
+<A NAME="IDX14"></A>
+This declaration is only useful when option <SAMP>`-t'</SAMP> (or, equivalently, the
+<SAMP>`%struct-type'</SAMP> declaration) has been given.
+It permits to specify initializers for the structure members following
+<VAR>slot-name</VAR> in empty hash table entries. The list of initializers
+should start with a comma. By default, the emitted code will
+zero-initialize structure members following <VAR>slot-name</VAR>.
+
+<DT><SAMP>`%define hash-function-name <VAR>name</VAR>'</SAMP>
+<DD>
+<A NAME="IDX15"></A>
+Allows you to specify the name for the generated hash function. Default
+name is <SAMP>`hash'</SAMP>. This option permits the use of two hash tables in
+the same file.
+
+<DT><SAMP>`%define lookup-function-name <VAR>name</VAR>'</SAMP>
+<DD>
+<A NAME="IDX16"></A>
+Allows you to specify the name for the generated lookup function.
+Default name is <SAMP>`in_word_set'</SAMP>. This option permits multiple
+generated hash functions to be used in the same application.
+
+<DT><SAMP>`%define class-name <VAR>name</VAR>'</SAMP>
+<DD>
+<A NAME="IDX17"></A>
+This option is only useful when option <SAMP>`-L C++'</SAMP> (or, equivalently,
+the <SAMP>`%language=C++'</SAMP> declaration) has been given. It
+allows you to specify the name of generated C++ class. Default name is
+<CODE>Perfect_Hash</CODE>.
+
+<DT><SAMP>`%7bit'</SAMP>
+<DD>
+<A NAME="IDX18"></A>
+This option specifies that all strings that will be passed as arguments
+to the generated hash function and the generated lookup function will
+solely consist of 7-bit ASCII characters (bytes in the range 0..127).
+(Note that the ANSI C functions <CODE>isalnum</CODE> and <CODE>isgraph</CODE> do
+<EM>not</EM> guarantee that a byte is in this range. Only an explicit
+test like <SAMP>`c &#62;= 'A' &#38;&#38; c &#60;= 'Z''</SAMP> guarantees this.)
+
+<DT><SAMP>`%compare-lengths'</SAMP>
+<DD>
+<A NAME="IDX19"></A>
+Compare keyword lengths before trying a string comparison. This option
+is mandatory for binary comparisons (see section <A HREF="gperf.html#SEC17">3.3 Use of NUL bytes</A>). It also might
+cut down on the number of string comparisons made during the lookup, since
+keywords with different lengths are never compared via <CODE>strcmp</CODE>.
+However, using <SAMP>`%compare-lengths'</SAMP> might greatly increase the size of the
+generated C code if the lookup table range is large (which implies that
+the switch option <SAMP>`-S'</SAMP> or <SAMP>`%switch'</SAMP> is not enabled), since the length
+table contains as many elements as there are entries in the lookup table.
+
+<DT><SAMP>`%compare-strncmp'</SAMP>
+<DD>
+<A NAME="IDX20"></A>
+Generates C code that uses the <CODE>strncmp</CODE> function to perform
+string comparisons. The default action is to use <CODE>strcmp</CODE>.
+
+<DT><SAMP>`%readonly-tables'</SAMP>
+<DD>
+<A NAME="IDX21"></A>
+Makes the contents of all generated lookup tables constant, i.e.,
+"readonly". Many compilers can generate more efficient code for this
+by putting the tables in readonly memory.
+
+<DT><SAMP>`%enum'</SAMP>
+<DD>
+<A NAME="IDX22"></A>
+Define constant values using an enum local to the lookup function rather
+than with #defines. This also means that different lookup functions can
+reside in the same file. Thanks to James Clark <CODE>&#60;jjc@ai.mit.edu&#62;</CODE>.
+
+<DT><SAMP>`%includes'</SAMP>
+<DD>
+<A NAME="IDX23"></A>
+Include the necessary system include file, <CODE>&#60;string.h&#62;</CODE>, at the
+beginning of the code. By default, this is not done; the user must
+include this header file himself to allow compilation of the code.
+
+<DT><SAMP>`%global-table'</SAMP>
+<DD>
+<A NAME="IDX24"></A>
+Generate the static table of keywords as a static global variable,
+rather than hiding it inside of the lookup function (which is the
+default behavior).
+
+<DT><SAMP>`%pic'</SAMP>
+<DD>
+<A NAME="IDX25"></A>
+Optimize the generated table for inclusion in shared libraries. This
+reduces the startup time of programs using a shared library containing
+the generated code. If the <SAMP>`%struct-type'</SAMP> declaration (or,
+equivalently, the option <SAMP>`-t'</SAMP>) is also given, the first field of the
+user-defined struct must be of type <SAMP>`int'</SAMP>, not <SAMP>`char *'</SAMP>, because
+it will contain offsets into the string pool instead of actual strings.
+To convert such an offset to a string, you can use the expression
+<SAMP>`stringpool + <VAR>o</VAR>'</SAMP>, where <VAR>o</VAR> is the offset. The string pool
+name can be changed through the <SAMP>`%define string-pool-name'</SAMP> declaration.
+
+<DT><SAMP>`%define string-pool-name <VAR>name</VAR>'</SAMP>
+<DD>
+<A NAME="IDX26"></A>
+Allows you to specify the name of the generated string pool created by
+the declaration <SAMP>`%pic'</SAMP> (or, equivalently, the option <SAMP>`-P'</SAMP>).
+The default name is <SAMP>`stringpool'</SAMP>. This declaration permits the use of
+two hash tables in the same file, with <SAMP>`%pic'</SAMP> and even when the
+<SAMP>`%global-table'</SAMP> declaration (or, equivalently, the option <SAMP>`-G'</SAMP>)
+is given.
+
+<DT><SAMP>`%null-strings'</SAMP>
+<DD>
+<A NAME="IDX27"></A>
+Use NULL strings instead of empty strings for empty keyword table entries.
+This reduces the startup time of programs using a shared library containing
+the generated code (but not as much as the declaration <SAMP>`%pic'</SAMP>), at the
+expense of one more test-and-branch instruction at run time.
+
+<DT><SAMP>`%define word-array-name <VAR>name</VAR>'</SAMP>
+<DD>
+<A NAME="IDX28"></A>
+Allows you to specify the name for the generated array containing the
+hash table. Default name is <SAMP>`wordlist'</SAMP>. This option permits the
+use of two hash tables in the same file, even when the option <SAMP>`-G'</SAMP>
+(or, equivalently, the <SAMP>`%global-table'</SAMP> declaration) is given.
+
+<DT><SAMP>`%switch=<VAR>count</VAR>'</SAMP>
+<DD>
+<A NAME="IDX29"></A>
+Causes the generated C code to use a <CODE>switch</CODE> statement scheme,
+rather than an array lookup table. This can lead to a reduction in both
+time and space requirements for some input files. The argument to this
+option determines how many <CODE>switch</CODE> statements are generated. A
+value of 1 generates 1 <CODE>switch</CODE> containing all the elements, a
+value of 2 generates 2 tables with 1/2 the elements in each
+<CODE>switch</CODE>, etc. This is useful since many C compilers cannot
+correctly generate code for large <CODE>switch</CODE> statements. This option
+was inspired in part by Keith Bostic's original C program.
+
+<DT><SAMP>`%omit-struct-type'</SAMP>
+<DD>
+<A NAME="IDX30"></A>
+Prevents the transfer of the type declaration to the output file. Use
+this option if the type is already defined elsewhere.
+</DL>
+
+
+
+<H4><A NAME="SEC12" HREF="gperf.html#TOC12">3.1.1.3 C Code Inclusion</A></H4>
+
+<P>
+<A NAME="IDX31"></A>
+<A NAME="IDX32"></A>
+Using a syntax similar to GNU utilities <CODE>flex</CODE> and <CODE>bison</CODE>, it
+is possible to directly include C source text and comments verbatim into
+the generated output file. This is accomplished by enclosing the region
+inside left-justified surrounding <SAMP>`%{'</SAMP>, <SAMP>`%}'</SAMP> pairs. Here is
+an input fragment based on the previous example that illustrates this
+feature:
+
+
+
+<PRE>
+%{
+#include &#60;assert.h&#62;
+/* This section of code is inserted directly into the output. */
+int return_month_days (struct month *months, int is_leap_year);
+%}
+struct month { char *name; int number; int days; int leap_days; };
+%%
+january, 1, 31, 31
+february, 2, 28, 29
+march, 3, 31, 31
+...
+</PRE>
+
+
+
+<H3><A NAME="SEC13" HREF="gperf.html#TOC13">3.1.2 Format for Keyword Entries</A></H3>
+
+<P>
+The second input file format section contains lines of keywords and any
+associated attributes you might supply. A line beginning with <SAMP>`#'</SAMP>
+in the first column is considered a comment. Everything following the
+<SAMP>`#'</SAMP> is ignored, up to and including the following newline. A line
+beginning with <SAMP>`%'</SAMP> in the first column is an option declaration and
+must not occur within the keywords section.
+
+
+<P>
+The first field of each non-comment line is always the keyword itself. It
+can be given in two ways: as a simple name, i.e., without surrounding
+string quotation marks, or as a string enclosed in double-quotes, in
+C syntax, possibly with backslash escapes like <CODE>\"</CODE> or <CODE>\234</CODE>
+or <CODE>\xa8</CODE>. In either case, it must start right at the beginning
+of the line, without leading whitespace.
+In this context, a "field" is considered to extend up to, but
+not include, the first blank, comma, or newline. Here is a simple
+example taken from a partial list of C reserved words:
+
+
+
+<PRE>
+# These are a few C reserved words, see the c.gperf file
+# for a complete list of ANSI C reserved words.
+unsigned
+sizeof
+switch
+signed
+if
+default
+for
+while
+return
+</PRE>
+
+<P>
+Note that unlike <CODE>flex</CODE> or <CODE>bison</CODE> the first <SAMP>`%%'</SAMP> marker
+may be elided if the declaration section is empty.
+
+
+<P>
+Additional fields may optionally follow the leading keyword. Fields
+should be separated by commas, and terminate at the end of line. What
+these fields mean is entirely up to you; they are used to initialize the
+elements of the user-defined <CODE>struct</CODE> provided by you in the
+declaration section. If the <SAMP>`-t'</SAMP> option (or, equivalently, the
+<SAMP>`%struct-type'</SAMP> declaration) is <EM>not</EM> enabled
+these fields are simply ignored. All previous examples except the last
+one contain keyword attributes.
+
+
+
+
+<H3><A NAME="SEC14" HREF="gperf.html#TOC14">3.1.3 Including Additional C Functions</A></H3>
+
+<P>
+The optional third section also corresponds closely with conventions
+found in <CODE>flex</CODE> and <CODE>bison</CODE>. All text in this section,
+starting at the final <SAMP>`%%'</SAMP> and extending to the end of the input
+file, is included verbatim into the generated output file. Naturally,
+it is your responsibility to ensure that the code contained in this
+section is valid C.
+
+
+
+
+<H3><A NAME="SEC15" HREF="gperf.html#TOC15">3.1.4 Where to place directives for GNU <CODE>indent</CODE>.</A></H3>
+
+<P>
+If you want to invoke GNU <CODE>indent</CODE> on a <CODE>gperf</CODE> input file,
+you will see that GNU <CODE>indent</CODE> doesn't understand the <SAMP>`%%'</SAMP>,
+<SAMP>`%{'</SAMP> and <SAMP>`%}'</SAMP> directives that control <CODE>gperf</CODE>'s
+interpretation of the input file. Therefore you have to insert some
+directives for GNU <CODE>indent</CODE>. More precisely, assuming the most
+general input file structure
+
+
+
+<PRE>
+declarations part 1
+%{
+verbatim code
+%}
+declarations part 2
+%%
+keywords
+%%
+functions
+</PRE>
+
+<P>
+you would insert <SAMP>`*INDENT-OFF*'</SAMP> and <SAMP>`*INDENT-ON*'</SAMP> comments
+as follows:
+
+
+
+<PRE>
+/* *INDENT-OFF* */
+declarations part 1
+%{
+/* *INDENT-ON* */
+verbatim code
+/* *INDENT-OFF* */
+%}
+declarations part 2
+%%
+keywords
+%%
+/* *INDENT-ON* */
+functions
+</PRE>
+
+
+
+<H2><A NAME="SEC16" HREF="gperf.html#TOC16">3.2 Output Format for Generated C Code with <CODE>gperf</CODE></A></H2>
+<P>
+<A NAME="IDX33"></A>
+
+
+<P>
+Several options control how the generated C code appears on the standard
+output. Two C function are generated. They are called <CODE>hash</CODE> and
+<CODE>in_word_set</CODE>, although you may modify their names with a command-line
+option. Both functions require two arguments, a string, <CODE>char *</CODE>
+<VAR>str</VAR>, and a length parameter, <CODE>int</CODE> <VAR>len</VAR>. Their default
+function prototypes are as follows:
+
+
+<P>
+<DL>
+<DT><U>Function:</U> unsigned int <B>hash</B> <I>(const char * <VAR>str</VAR>, unsigned int <VAR>len</VAR>)</I>
+<DD><A NAME="IDX34"></A>
+By default, the generated <CODE>hash</CODE> function returns an integer value
+created by adding <VAR>len</VAR> to several user-specified <VAR>str</VAR> byte
+positions indexed into an <EM>associated values</EM> table stored in a
+local static array. The associated values table is constructed
+internally by <CODE>gperf</CODE> and later output as a static local C array
+called <SAMP>`hash_table'</SAMP>. The relevant selected positions (i.e. indices
+into <VAR>str</VAR>) are specified via the <SAMP>`-k'</SAMP> option when running
+<CODE>gperf</CODE>, as detailed in the <EM>Options</EM> section below (see section <A HREF="gperf.html#SEC18">4. Invoking <CODE>gperf</CODE></A>).
+</DL>
+
+
+<P>
+<DL>
+<DT><U>Function:</U> <B>in_word_set</B> <I>(const char * <VAR>str</VAR>, unsigned int <VAR>len</VAR>)</I>
+<DD><A NAME="IDX35"></A>
+If <VAR>str</VAR> is in the keyword set, returns a pointer to that
+keyword. More exactly, if the option <SAMP>`-t'</SAMP> (or, equivalently, the
+<SAMP>`%struct-type'</SAMP> declaration) was given, it returns
+a pointer to the matching keyword's structure. Otherwise it returns
+<CODE>NULL</CODE>.
+</DL>
+
+
+<P>
+If the option <SAMP>`-c'</SAMP> (or, equivalently, the <SAMP>`%compare-strncmp'</SAMP>
+declaration) is not used, <VAR>str</VAR> must be a NUL terminated
+string of exactly length <VAR>len</VAR>. If <SAMP>`-c'</SAMP> (or, equivalently, the
+<SAMP>`%compare-strncmp'</SAMP> declaration) is used, <VAR>str</VAR> must
+simply be an array of <VAR>len</VAR> bytes and does not need to be NUL
+terminated.
+
+
+<P>
+The code generated for these two functions is affected by the following
+options:
+
+
+<DL COMPACT>
+
+<DT><SAMP>`-t'</SAMP>
+<DD>
+<DT><SAMP>`--struct-type'</SAMP>
+<DD>
+Make use of the user-defined <CODE>struct</CODE>.
+
+<DT><SAMP>`-S <VAR>total-switch-statements</VAR>'</SAMP>
+<DD>
+<DT><SAMP>`--switch=<VAR>total-switch-statements</VAR>'</SAMP>
+<DD>
+<A NAME="IDX36"></A>
+Generate 1 or more C <CODE>switch</CODE> statement rather than use a large,
+(and potentially sparse) static array. Although the exact time and
+space savings of this approach vary according to your C compiler's
+degree of optimization, this method often results in smaller and faster
+code.
+</DL>
+
+<P>
+If the <SAMP>`-t'</SAMP> and <SAMP>`-S'</SAMP> options (or, equivalently, the
+<SAMP>`%struct-type'</SAMP> and <SAMP>`%switch'</SAMP> declarations) are omitted, the default
+action
+is to generate a <CODE>char *</CODE> array containing the keywords, together with
+additional empty strings used for padding the array. By experimenting
+with the various input and output options, and timing the resulting C
+code, you can determine the best option choices for different keyword
+set characteristics.
+
+
+
+
+<H2><A NAME="SEC17" HREF="gperf.html#TOC17">3.3 Use of NUL bytes</A></H2>
+<P>
+<A NAME="IDX37"></A>
+
+
+<P>
+By default, the code generated by <CODE>gperf</CODE> operates on zero
+terminated strings, the usual representation of strings in C. This means
+that the keywords in the input file must not contain NUL bytes,
+and the <VAR>str</VAR> argument passed to <CODE>hash</CODE> or <CODE>in_word_set</CODE>
+must be NUL terminated and have exactly length <VAR>len</VAR>.
+
+
+<P>
+If option <SAMP>`-c'</SAMP> (or, equivalently, the <SAMP>`%compare-strncmp'</SAMP>
+declaration) is used, then the <VAR>str</VAR> argument does not need
+to be NUL terminated. The code generated by <CODE>gperf</CODE> will only
+access the first <VAR>len</VAR>, not <VAR>len+1</VAR>, bytes starting at <VAR>str</VAR>.
+However, the keywords in the input file still must not contain NUL
+bytes.
+
+
+<P>
+If option <SAMP>`-l'</SAMP> (or, equivalently, the <SAMP>`%compare-lengths'</SAMP>
+declaration) is used, then the hash table performs binary
+comparison. The keywords in the input file may contain NUL bytes,
+written in string syntax as <CODE>\000</CODE> or <CODE>\x00</CODE>, and the code
+generated by <CODE>gperf</CODE> will treat NUL like any other byte.
+Also, in this case the <SAMP>`-c'</SAMP> option (or, equivalently, the
+<SAMP>`%compare-strncmp'</SAMP> declaration) is ignored.
+
+
+
+
+<H1><A NAME="SEC18" HREF="gperf.html#TOC18">4. Invoking <CODE>gperf</CODE></A></H1>
+
+<P>
+There are <EM>many</EM> options to <CODE>gperf</CODE>. They were added to make
+the program more convenient for use with real applications. "On-line"
+help is readily available via the <SAMP>`--help'</SAMP> option. Here is the
+complete list of options.
+
+
+
+
+<H2><A NAME="SEC19" HREF="gperf.html#TOC19">4.1 Specifying the Location of the Output File</A></H2>
+
+<DL COMPACT>
+
+<DT><SAMP>`--output-file=<VAR>file</VAR>'</SAMP>
+<DD>
+Allows you to specify the name of the file to which the output is written to.
+</DL>
+
+<P>
+The results are written to standard output if no output file is specified
+or if it is <SAMP>`-'</SAMP>.
+
+
+
+
+<H2><A NAME="SEC20" HREF="gperf.html#TOC20">4.2 Options that affect Interpretation of the Input File</A></H2>
+
+<P>
+These options are also available as declarations in the input file
+(see section <A HREF="gperf.html#SEC11">3.1.1.2 Gperf Declarations</A>).
+
+
+<DL COMPACT>
+
+<DT><SAMP>`-e <VAR>keyword-delimiter-list</VAR>'</SAMP>
+<DD>
+<DT><SAMP>`--delimiters=<VAR>keyword-delimiter-list</VAR>'</SAMP>
+<DD>
+<A NAME="IDX38"></A>
+Allows you to provide a string containing delimiters used to
+separate keywords from their attributes. The default is ",". This
+option is essential if you want to use keywords that have embedded
+commas or newlines. One useful trick is to use -e'TAB', where TAB is
+the literal tab character.
+
+<DT><SAMP>`-t'</SAMP>
+<DD>
+<DT><SAMP>`--struct-type'</SAMP>
+<DD>
+Allows you to include a <CODE>struct</CODE> type declaration for generated
+code. Any text before a pair of consecutive <SAMP>`%%'</SAMP> is considered
+part of the type declaration. Keywords and additional fields may follow
+this, one group of fields per line. A set of examples for generating
+perfect hash tables and functions for Ada, C, C++, Pascal, Modula 2,
+Modula 3 and JavaScript reserved words are distributed with this release.
+
+<DT><SAMP>`--ignore-case'</SAMP>
+<DD>
+Consider upper and lower case ASCII characters as equivalent. The string
+comparison will use a case insignificant character comparison. Note that
+locale dependent case mappings are ignored. This option is therefore not
+suitable if a properly internationalized or locale aware case mapping
+should be used. (For example, in a Turkish locale, the upper case equivalent
+of the lowercase ASCII letter <SAMP>`i'</SAMP> is the non-ASCII character
+<SAMP>`capital i with dot above'</SAMP>.) For this case, it is better to apply
+an uppercase or lowercase conversion on the string before passing it to
+the <CODE>gperf</CODE> generated function.
+</DL>
+
+
+
+<H2><A NAME="SEC21" HREF="gperf.html#TOC21">4.3 Options to specify the Language for the Output Code</A></H2>
+
+<P>
+These options are also available as declarations in the input file
+(see section <A HREF="gperf.html#SEC11">3.1.1.2 Gperf Declarations</A>).
+
+
+<DL COMPACT>
+
+<DT><SAMP>`-L <VAR>generated-language-name</VAR>'</SAMP>
+<DD>
+<DT><SAMP>`--language=<VAR>generated-language-name</VAR>'</SAMP>
+<DD>
+Instructs <CODE>gperf</CODE> to generate code in the language specified by the
+option's argument. Languages handled are currently:
+
+<DL COMPACT>
+
+<DT><SAMP>`KR-C'</SAMP>
+<DD>
+Old-style K&#38;R C. This language is understood by old-style C compilers and
+ANSI C compilers, but ANSI C compilers may flag warnings (or even errors)
+because of lacking <SAMP>`const'</SAMP>.
+
+<DT><SAMP>`C'</SAMP>
+<DD>
+Common C. This language is understood by ANSI C compilers, and also by
+old-style C compilers, provided that you <CODE>#define const</CODE> to empty
+for compilers which don't know about this keyword.
+
+<DT><SAMP>`ANSI-C'</SAMP>
+<DD>
+ANSI C. This language is understood by ANSI C compilers and C++ compilers.
+
+<DT><SAMP>`C++'</SAMP>
+<DD>
+C++. This language is understood by C++ compilers.
+</DL>
+
+The default is C.
+
+<DT><SAMP>`-a'</SAMP>
+<DD>
+This option is supported for compatibility with previous releases of
+<CODE>gperf</CODE>. It does not do anything.
+
+<DT><SAMP>`-g'</SAMP>
+<DD>
+This option is supported for compatibility with previous releases of
+<CODE>gperf</CODE>. It does not do anything.
+</DL>
+
+
+
+<H2><A NAME="SEC22" HREF="gperf.html#TOC22">4.4 Options for fine tuning Details in the Output Code</A></H2>
+
+<P>
+Most of these options are also available as declarations in the input file
+(see section <A HREF="gperf.html#SEC11">3.1.1.2 Gperf Declarations</A>).
+
+
+<DL COMPACT>
+
+<DT><SAMP>`-K <VAR>slot-name</VAR>'</SAMP>
+<DD>
+<DT><SAMP>`--slot-name=<VAR>slot-name</VAR>'</SAMP>
+<DD>
+<A NAME="IDX39"></A>
+This option is only useful when option <SAMP>`-t'</SAMP> (or, equivalently, the
+<SAMP>`%struct-type'</SAMP> declaration) has been given.
+By default, the program assumes the structure component identifier for
+the keyword is <SAMP>`name'</SAMP>. This option allows an arbitrary choice of
+identifier for this component, although it still must occur as the first
+field in your supplied <CODE>struct</CODE>.
+
+<DT><SAMP>`-F <VAR>initializers</VAR>'</SAMP>
+<DD>
+<DT><SAMP>`--initializer-suffix=<VAR>initializers</VAR>'</SAMP>
+<DD>
+<A NAME="IDX40"></A>
+This option is only useful when option <SAMP>`-t'</SAMP> (or, equivalently, the
+<SAMP>`%struct-type'</SAMP> declaration) has been given.
+It permits to specify initializers for the structure members following
+<VAR>slot-name</VAR> in empty hash table entries. The list of initializers
+should start with a comma. By default, the emitted code will
+zero-initialize structure members following <VAR>slot-name</VAR>.
+
+<DT><SAMP>`-H <VAR>hash-function-name</VAR>'</SAMP>
+<DD>
+<DT><SAMP>`--hash-function-name=<VAR>hash-function-name</VAR>'</SAMP>
+<DD>
+Allows you to specify the name for the generated hash function. Default
+name is <SAMP>`hash'</SAMP>. This option permits the use of two hash tables in
+the same file.
+
+<DT><SAMP>`-N <VAR>lookup-function-name</VAR>'</SAMP>
+<DD>
+<DT><SAMP>`--lookup-function-name=<VAR>lookup-function-name</VAR>'</SAMP>
+<DD>
+Allows you to specify the name for the generated lookup function.
+Default name is <SAMP>`in_word_set'</SAMP>. This option permits multiple
+generated hash functions to be used in the same application.
+
+<DT><SAMP>`-Z <VAR>class-name</VAR>'</SAMP>
+<DD>
+<DT><SAMP>`--class-name=<VAR>class-name</VAR>'</SAMP>
+<DD>
+<A NAME="IDX41"></A>
+This option is only useful when option <SAMP>`-L C++'</SAMP> (or, equivalently,
+the <SAMP>`%language=C++'</SAMP> declaration) has been given. It
+allows you to specify the name of generated C++ class. Default name is
+<CODE>Perfect_Hash</CODE>.
+
+<DT><SAMP>`-7'</SAMP>
+<DD>
+<DT><SAMP>`--seven-bit'</SAMP>
+<DD>
+This option specifies that all strings that will be passed as arguments
+to the generated hash function and the generated lookup function will
+solely consist of 7-bit ASCII characters (bytes in the range 0..127).
+(Note that the ANSI C functions <CODE>isalnum</CODE> and <CODE>isgraph</CODE> do
+<EM>not</EM> guarantee that a byte is in this range. Only an explicit
+test like <SAMP>`c &#62;= 'A' &#38;&#38; c &#60;= 'Z''</SAMP> guarantees this.) This was the
+default in versions of <CODE>gperf</CODE> earlier than 2.7; now the default is
+to support 8-bit and multibyte characters.
+
+<DT><SAMP>`-l'</SAMP>
+<DD>
+<DT><SAMP>`--compare-lengths'</SAMP>
+<DD>
+Compare keyword lengths before trying a string comparison. This option
+is mandatory for binary comparisons (see section <A HREF="gperf.html#SEC17">3.3 Use of NUL bytes</A>). It also might
+cut down on the number of string comparisons made during the lookup, since
+keywords with different lengths are never compared via <CODE>strcmp</CODE>.
+However, using <SAMP>`-l'</SAMP> might greatly increase the size of the
+generated C code if the lookup table range is large (which implies that
+the switch option <SAMP>`-S'</SAMP> or <SAMP>`%switch'</SAMP> is not enabled), since the length
+table contains as many elements as there are entries in the lookup table.
+
+<DT><SAMP>`-c'</SAMP>
+<DD>
+<DT><SAMP>`--compare-strncmp'</SAMP>
+<DD>
+Generates C code that uses the <CODE>strncmp</CODE> function to perform
+string comparisons. The default action is to use <CODE>strcmp</CODE>.
+
+<DT><SAMP>`-C'</SAMP>
+<DD>
+<DT><SAMP>`--readonly-tables'</SAMP>
+<DD>
+Makes the contents of all generated lookup tables constant, i.e.,
+"readonly". Many compilers can generate more efficient code for this
+by putting the tables in readonly memory.
+
+<DT><SAMP>`-E'</SAMP>
+<DD>
+<DT><SAMP>`--enum'</SAMP>
+<DD>
+Define constant values using an enum local to the lookup function rather
+than with #defines. This also means that different lookup functions can
+reside in the same file. Thanks to James Clark <CODE>&#60;jjc@ai.mit.edu&#62;</CODE>.
+
+<DT><SAMP>`-I'</SAMP>
+<DD>
+<DT><SAMP>`--includes'</SAMP>
+<DD>
+Include the necessary system include file, <CODE>&#60;string.h&#62;</CODE>, at the
+beginning of the code. By default, this is not done; the user must
+include this header file himself to allow compilation of the code.
+
+<DT><SAMP>`-G'</SAMP>
+<DD>
+<DT><SAMP>`--global-table'</SAMP>
+<DD>
+Generate the static table of keywords as a static global variable,
+rather than hiding it inside of the lookup function (which is the
+default behavior).
+
+<DT><SAMP>`-P'</SAMP>
+<DD>
+<DT><SAMP>`--pic'</SAMP>
+<DD>
+Optimize the generated table for inclusion in shared libraries. This
+reduces the startup time of programs using a shared library containing
+the generated code. If the option <SAMP>`-t'</SAMP> (or, equivalently, the
+<SAMP>`%struct-type'</SAMP> declaration) is also given, the first field of the
+user-defined struct must be of type <SAMP>`int'</SAMP>, not <SAMP>`char *'</SAMP>, because
+it will contain offsets into the string pool instead of actual strings.
+To convert such an offset to a string, you can use the expression
+<SAMP>`stringpool + <VAR>o</VAR>'</SAMP>, where <VAR>o</VAR> is the offset. The string pool
+name can be changed through the option <SAMP>`--string-pool-name'</SAMP>.
+
+<DT><SAMP>`-Q <VAR>string-pool-name</VAR>'</SAMP>
+<DD>
+<DT><SAMP>`--string-pool-name=<VAR>string-pool-name</VAR>'</SAMP>
+<DD>
+Allows you to specify the name of the generated string pool created by
+option <SAMP>`-P'</SAMP>. The default name is <SAMP>`stringpool'</SAMP>. This option
+permits the use of two hash tables in the same file, with <SAMP>`-P'</SAMP> and
+even when the option <SAMP>`-G'</SAMP> (or, equivalently, the <SAMP>`%global-table'</SAMP>
+declaration) is given.
+
+<DT><SAMP>`--null-strings'</SAMP>
+<DD>
+Use NULL strings instead of empty strings for empty keyword table entries.
+This reduces the startup time of programs using a shared library containing
+the generated code (but not as much as option <SAMP>`-P'</SAMP>), at the expense
+of one more test-and-branch instruction at run time.
+
+<DT><SAMP>`-W <VAR>hash-table-array-name</VAR>'</SAMP>
+<DD>
+<DT><SAMP>`--word-array-name=<VAR>hash-table-array-name</VAR>'</SAMP>
+<DD>
+<A NAME="IDX42"></A>
+Allows you to specify the name for the generated array containing the
+hash table. Default name is <SAMP>`wordlist'</SAMP>. This option permits the
+use of two hash tables in the same file, even when the option <SAMP>`-G'</SAMP>
+(or, equivalently, the <SAMP>`%global-table'</SAMP> declaration) is given.
+
+<DT><SAMP>`-S <VAR>total-switch-statements</VAR>'</SAMP>
+<DD>
+<DT><SAMP>`--switch=<VAR>total-switch-statements</VAR>'</SAMP>
+<DD>
+<A NAME="IDX43"></A>
+Causes the generated C code to use a <CODE>switch</CODE> statement scheme,
+rather than an array lookup table. This can lead to a reduction in both
+time and space requirements for some input files. The argument to this
+option determines how many <CODE>switch</CODE> statements are generated. A
+value of 1 generates 1 <CODE>switch</CODE> containing all the elements, a
+value of 2 generates 2 tables with 1/2 the elements in each
+<CODE>switch</CODE>, etc. This is useful since many C compilers cannot
+correctly generate code for large <CODE>switch</CODE> statements. This option
+was inspired in part by Keith Bostic's original C program.
+
+<DT><SAMP>`-T'</SAMP>
+<DD>
+<DT><SAMP>`--omit-struct-type'</SAMP>
+<DD>
+Prevents the transfer of the type declaration to the output file. Use
+this option if the type is already defined elsewhere.
+
+<DT><SAMP>`-p'</SAMP>
+<DD>
+This option is supported for compatibility with previous releases of
+<CODE>gperf</CODE>. It does not do anything.
+</DL>
+
+
+
+<H2><A NAME="SEC23" HREF="gperf.html#TOC23">4.5 Options for changing the Algorithms employed by <CODE>gperf</CODE></A></H2>
+
+<DL COMPACT>
+
+<DT><SAMP>`-k <VAR>selected-byte-positions</VAR>'</SAMP>
+<DD>
+<DT><SAMP>`--key-positions=<VAR>selected-byte-positions</VAR>'</SAMP>
+<DD>
+Allows selection of the byte positions used in the keywords'
+hash function. The allowable choices range between 1-255, inclusive.
+The positions are separated by commas, e.g., <SAMP>`-k 9,4,13,14'</SAMP>;
+ranges may be used, e.g., <SAMP>`-k 2-7'</SAMP>; and positions may occur
+in any order. Furthermore, the wildcard '*' causes the generated
+hash function to consider <STRONG>all</STRONG> byte positions in each keyword,
+whereas '$' instructs the hash function to use the "final byte"
+of a keyword (this is the only way to use a byte position greater than
+255, incidentally).
+
+For instance, the option <SAMP>`-k 1,2,4,6-10,'$''</SAMP> generates a hash
+function that considers positions 1,2,4,6,7,8,9,10, plus the last
+byte in each keyword (which may be at a different position for each
+keyword, obviously). Keywords
+with length less than the indicated byte positions work properly, since
+selected byte positions exceeding the keyword length are simply not
+referenced in the hash function.
+
+This option is not normally needed since version 2.8 of <CODE>gperf</CODE>;
+the default byte positions are computed depending on the keyword set,
+through a search that minimizes the number of byte positions.
+
+<DT><SAMP>`-D'</SAMP>
+<DD>
+<DT><SAMP>`--duplicates'</SAMP>
+<DD>
+<A NAME="IDX44"></A>
+Handle keywords whose selected byte sets hash to duplicate values.
+Duplicate hash values can occur if a set of keywords has the same names, but
+possesses different attributes, or if the selected byte positions are not well
+chosen. With the -D option <CODE>gperf</CODE> treats all these keywords as
+part of an equivalence class and generates a perfect hash function with
+multiple comparisons for duplicate keywords. It is up to you to completely
+disambiguate the keywords by modifying the generated C code. However,
+<CODE>gperf</CODE> helps you out by organizing the output.
+
+Using this option usually means that the generated hash function is no
+longer perfect. On the other hand, it permits <CODE>gperf</CODE> to work on
+keyword sets that it otherwise could not handle.
+
+<DT><SAMP>`-m <VAR>iterations</VAR>'</SAMP>
+<DD>
+<DT><SAMP>`--multiple-iterations=<VAR>iterations</VAR>'</SAMP>
+<DD>
+Perform multiple choices of the <SAMP>`-i'</SAMP> and <SAMP>`-j'</SAMP> values, and
+choose the best results. This increases the running time by a factor of
+<VAR>iterations</VAR> but does a good job minimizing the generated table size.
+
+<DT><SAMP>`-i <VAR>initial-value</VAR>'</SAMP>
+<DD>
+<DT><SAMP>`--initial-asso=<VAR>initial-value</VAR>'</SAMP>
+<DD>
+Provides an initial <VAR>value</VAR> for the associate values array. Default
+is 0. Increasing the initial value helps inflate the final table size,
+possibly leading to more time efficient keyword lookups. Note that this
+option is not particularly useful when <SAMP>`-S'</SAMP> (or, equivalently,
+<SAMP>`%switch'</SAMP>) is used. Also,
+<SAMP>`-i'</SAMP> is overridden when the <SAMP>`-r'</SAMP> option is used.
+
+<DT><SAMP>`-j <VAR>jump-value</VAR>'</SAMP>
+<DD>
+<DT><SAMP>`--jump=<VAR>jump-value</VAR>'</SAMP>
+<DD>
+<A NAME="IDX45"></A>
+Affects the "jump value", i.e., how far to advance the associated
+byte value upon collisions. <VAR>Jump-value</VAR> is rounded up to an
+odd number, the default is 5. If the <VAR>jump-value</VAR> is 0 <CODE>gperf</CODE>
+jumps by random amounts.
+
+<DT><SAMP>`-n'</SAMP>
+<DD>
+<DT><SAMP>`--no-strlen'</SAMP>
+<DD>
+Instructs the generator not to include the length of a keyword when
+computing its hash value. This may save a few assembly instructions in
+the generated lookup table.
+
+<DT><SAMP>`-r'</SAMP>
+<DD>
+<DT><SAMP>`--random'</SAMP>
+<DD>
+Utilizes randomness to initialize the associated values table. This
+frequently generates solutions faster than using deterministic
+initialization (which starts all associated values at 0). Furthermore,
+using the randomization option generally increases the size of the
+table.
+
+<DT><SAMP>`-s <VAR>size-multiple</VAR>'</SAMP>
+<DD>
+<DT><SAMP>`--size-multiple=<VAR>size-multiple</VAR>'</SAMP>
+<DD>
+Affects the size of the generated hash table. The numeric argument for
+this option indicates "how many times larger or smaller" the maximum
+associated value range should be, in relationship to the number of keywords.
+It can be written as an integer, a floating-point number or a fraction.
+For example, a value of 3 means "allow the maximum associated value to be
+about 3 times larger than the number of input keywords".
+Conversely, a value of 1/3 means "allow the maximum associated value to
+be about 3 times smaller than the number of input keywords". Values
+smaller than 1 are useful for limiting the overall size of the generated hash
+table, though the option <SAMP>`-m'</SAMP> is better at this purpose.
+
+If `generate switch' option <SAMP>`-S'</SAMP> (or, equivalently, <SAMP>`%switch'</SAMP>) is
+<EM>not</EM> enabled, the maximum
+associated value influences the static array table size, and a larger
+table should decrease the time required for an unsuccessful search, at
+the expense of extra table space.
+
+The default value is 1, thus the default maximum associated value about
+the same size as the number of keywords (for efficiency, the maximum
+associated value is always rounded up to a power of 2). The actual
+table size may vary somewhat, since this technique is essentially a
+heuristic.
+</DL>
+
+
+
+<H2><A NAME="SEC24" HREF="gperf.html#TOC24">4.6 Informative Output</A></H2>
+
+<DL COMPACT>
+
+<DT><SAMP>`-h'</SAMP>
+<DD>
+<DT><SAMP>`--help'</SAMP>
+<DD>
+Prints a short summary on the meaning of each program option. Aborts
+further program execution.
+
+<DT><SAMP>`-v'</SAMP>
+<DD>
+<DT><SAMP>`--version'</SAMP>
+<DD>
+Prints out the current version number.
+
+<DT><SAMP>`-d'</SAMP>
+<DD>
+<DT><SAMP>`--debug'</SAMP>
+<DD>
+Enables the debugging option. This produces verbose diagnostics to
+"standard error" when <CODE>gperf</CODE> is executing. It is useful both for
+maintaining the program and for determining whether a given set of
+options is actually speeding up the search for a solution. Some useful
+information is dumped at the end of the program when the <SAMP>`-d'</SAMP>
+option is enabled.
+</DL>
+
+
+
+<H1><A NAME="SEC25" HREF="gperf.html#TOC25">5. Known Bugs and Limitations with <CODE>gperf</CODE></A></H1>
+
+<P>
+The following are some limitations with the current release of
+<CODE>gperf</CODE>:
+
+
+
+<UL>
+<LI>
+
+The <CODE>gperf</CODE> utility is tuned to execute quickly, and works quickly
+for small to medium size data sets (around 1000 keywords). It is
+extremely useful for maintaining perfect hash functions for compiler
+keyword sets. Several recent enhancements now enable <CODE>gperf</CODE> to
+work efficiently on much larger keyword sets (over 15,000 keywords).
+When processing large keyword sets it helps greatly to have over 8 megs
+of RAM.
+
+<LI>
+
+The size of the generate static keyword array can get <EM>extremely</EM>
+large if the input keyword file is large or if the keywords are quite
+similar. This tends to slow down the compilation of the generated C
+code, and <EM>greatly</EM> inflates the object code size. If this
+situation occurs, consider using the <SAMP>`-S'</SAMP> option to reduce data
+size, potentially increasing keyword recognition time a negligible
+amount. Since many C compilers cannot correctly generate code for
+large switch statements it is important to qualify the <VAR>-S</VAR> option
+with an appropriate numerical argument that controls the number of
+switch statements generated.
+
+<LI>
+
+The maximum number of selected byte positions has an
+arbitrary limit of 255. This restriction should be removed, and if
+anyone considers this a problem write me and let me know so I can remove
+the constraint.
+</UL>
+
+
+
+<H1><A NAME="SEC26" HREF="gperf.html#TOC26">6. Things Still Left to Do</A></H1>
+
+<P>
+It should be "relatively" easy to replace the current perfect hash
+function algorithm with a more exhaustive approach; the perfect hash
+module is essential independent from other program modules. Additional
+worthwhile improvements include:
+
+
+
+<UL>
+<LI>
+
+Another useful extension involves modifying the program to generate
+"minimal" perfect hash functions (under certain circumstances, the
+current version can be rather extravagant in the generated table size).
+This is mostly of theoretical interest, since a sparse table
+often produces faster lookups, and use of the <SAMP>`-S'</SAMP> <CODE>switch</CODE>
+option can minimize the data size, at the expense of slightly longer
+lookups (note that the gcc compiler generally produces good code for
+<CODE>switch</CODE> statements, reducing the need for more complex schemes).
+
+<LI>
+
+In addition to improving the algorithm, it would also be useful to
+generate an Ada package as the code output, in addition to the current
+C and C++ routines.
+</UL>
+
+
+
+<H1><A NAME="SEC27" HREF="gperf.html#TOC27">7. Bibliography</A></H1>
+
+<P>
+[1] Chang, C.C.: <I>A Scheme for Constructing Ordered Minimal Perfect
+Hashing Functions</I> Information Sciences 39(1986), 187-195.
+
+
+<P>
+[2] Cichelli, Richard J. <I>Author's Response to "On Cichelli's Minimal Perfect Hash
+Functions Method"</I> Communications of the ACM, 23, 12(December 1980), 729.
+
+
+<P>
+[3] Cichelli, Richard J. <I>Minimal Perfect Hash Functions Made Simple</I>
+Communications of the ACM, 23, 1(January 1980), 17-19.
+
+
+<P>
+[4] Cook, C. R. and Oldehoeft, R.R. <I>A Letter Oriented Minimal
+Perfect Hashing Function</I> SIGPLAN Notices, 17, 9(September 1982), 18-27.
+
+
+<P>
+[5] Cormack, G. V. and Horspool, R. N. S. and Kaiserwerth, M.
+<I>Practical Perfect Hashing</I> Computer Journal, 28, 1(January 1985), 54-58.
+
+
+<P>
+[6] Jaeschke, G. <I>Reciprocal Hashing: A Method for Generating Minimal
+Perfect Hashing Functions</I> Communications of the ACM, 24, 12(December
+1981), 829-833.
+
+
+<P>
+[7] Jaeschke, G. and Osterburg, G. <I>On Cichelli's Minimal Perfect
+Hash Functions Method</I> Communications of the ACM, 23, 12(December 1980),
+728-729.
+
+
+<P>
+[8] Sager, Thomas J. <I>A Polynomial Time Generator for Minimal Perfect
+Hash Functions</I> Communications of the ACM, 28, 5(December 1985), 523-532
+
+
+<P>
+[9] Schmidt, Douglas C. <I>GPERF: A Perfect Hash Function Generator</I>
+Second USENIX C++ Conference Proceedings, April 1990.
+
+
+<P>
+[10] Schmidt, Douglas C. <I>GPERF: A Perfect Hash Function Generator</I>
+C++ Report, SIGS 10 10 (November/December 1998).
+
+
+<P>
+[11] Sebesta, R.W. and Taylor, M.A. <I>Minimal Perfect Hash Functions
+for Reserved Word Lists</I> SIGPLAN Notices, 20, 12(September 1985), 47-53.
+
+
+<P>
+[12] Sprugnoli, R. <I>Perfect Hashing Functions: A Single Probe
+Retrieving Method for Static Sets</I> Communications of the ACM, 20
+11(November 1977), 841-850.
+
+
+<P>
+[13] Stallman, Richard M. <I>Using and Porting GNU CC</I> Free Software Foundation,
+1988.
+
+
+<P>
+[14] Stroustrup, Bjarne <I>The C++ Programming Language.</I> Addison-Wesley, 1986.
+
+
+<P>
+[15] Tiemann, Michael D. <I>User's Guide to GNU C++</I> Free Software
+Foundation, 1989.
+
+
+
+
+<H1><A NAME="SEC28" HREF="gperf.html#TOC28">Concept Index</A></H1>
+
+<P>
+Jump to:
+<A HREF="#cindex_%">%</A>
+-
+<A HREF="#cindex_a">a</A>
+-
+<A HREF="#cindex_b">b</A>
+-
+<A HREF="#cindex_c">c</A>
+-
+<A HREF="#cindex_d">d</A>
+-
+<A HREF="#cindex_f">f</A>
+-
+<A HREF="#cindex_h">h</A>
+-
+<A HREF="#cindex_i">i</A>
+-
+<A HREF="#cindex_j">j</A>
+-
+<A HREF="#cindex_k">k</A>
+-
+<A HREF="#cindex_m">m</A>
+-
+<A HREF="#cindex_n">n</A>
+-
+<A HREF="#cindex_s">s</A>
+<P>
+<H2><A NAME="cindex_%">%</A></H2>
+<DIR>
+<LI><A HREF="gperf.html#IDX8"><SAMP>`%%'</SAMP></A>
+<LI><A HREF="gperf.html#IDX18"><SAMP>`%7bit'</SAMP></A>
+<LI><A HREF="gperf.html#IDX19"><SAMP>`%compare-lengths'</SAMP></A>
+<LI><A HREF="gperf.html#IDX20"><SAMP>`%compare-strncmp'</SAMP></A>
+<LI><A HREF="gperf.html#IDX17"><SAMP>`%define class-name'</SAMP></A>
+<LI><A HREF="gperf.html#IDX15"><SAMP>`%define hash-function-name'</SAMP></A>
+<LI><A HREF="gperf.html#IDX14"><SAMP>`%define initializer-suffix'</SAMP></A>
+<LI><A HREF="gperf.html#IDX16"><SAMP>`%define lookup-function-name'</SAMP></A>
+<LI><A HREF="gperf.html#IDX13"><SAMP>`%define slot-name'</SAMP></A>
+<LI><A HREF="gperf.html#IDX26"><SAMP>`%define string-pool-name'</SAMP></A>
+<LI><A HREF="gperf.html#IDX28"><SAMP>`%define word-array-name'</SAMP></A>
+<LI><A HREF="gperf.html#IDX9"><SAMP>`%delimiters'</SAMP></A>
+<LI><A HREF="gperf.html#IDX22"><SAMP>`%enum'</SAMP></A>
+<LI><A HREF="gperf.html#IDX24"><SAMP>`%global-table'</SAMP></A>
+<LI><A HREF="gperf.html#IDX11"><SAMP>`%ignore-case'</SAMP></A>
+<LI><A HREF="gperf.html#IDX23"><SAMP>`%includes'</SAMP></A>
+<LI><A HREF="gperf.html#IDX12"><SAMP>`%language'</SAMP></A>
+<LI><A HREF="gperf.html#IDX27"><SAMP>`%null-strings'</SAMP></A>
+<LI><A HREF="gperf.html#IDX30"><SAMP>`%omit-struct-type'</SAMP></A>
+<LI><A HREF="gperf.html#IDX25"><SAMP>`%pic'</SAMP></A>
+<LI><A HREF="gperf.html#IDX21"><SAMP>`%readonly-tables'</SAMP></A>
+<LI><A HREF="gperf.html#IDX10"><SAMP>`%struct-type'</SAMP></A>
+<LI><A HREF="gperf.html#IDX29"><SAMP>`%switch'</SAMP></A>
+<LI><A HREF="gperf.html#IDX31"><SAMP>`%{'</SAMP></A>
+<LI><A HREF="gperf.html#IDX32"><SAMP>`%}'</SAMP></A>
+</DIR>
+<H2><A NAME="cindex_a">a</A></H2>
+<DIR>
+<LI><A HREF="gperf.html#IDX42">Array name</A>
+</DIR>
+<H2><A NAME="cindex_b">b</A></H2>
+<DIR>
+<LI><A HREF="gperf.html#IDX1">Bugs</A>
+</DIR>
+<H2><A NAME="cindex_c">c</A></H2>
+<DIR>
+<LI><A HREF="gperf.html#IDX41">Class name</A>
+</DIR>
+<H2><A NAME="cindex_d">d</A></H2>
+<DIR>
+<LI><A HREF="gperf.html#IDX5">Declaration section</A>
+<LI><A HREF="gperf.html#IDX38">Delimiters</A>
+<LI><A HREF="gperf.html#IDX44">Duplicates</A>
+</DIR>
+<H2><A NAME="cindex_f">f</A></H2>
+<DIR>
+<LI><A HREF="gperf.html#IDX4">Format</A>
+<LI><A HREF="gperf.html#IDX7">Functions section</A>
+</DIR>
+<H2><A NAME="cindex_h">h</A></H2>
+<DIR>
+<LI><A HREF="gperf.html#IDX34">hash</A>
+<LI><A HREF="gperf.html#IDX33">hash table</A>
+</DIR>
+<H2><A NAME="cindex_i">i</A></H2>
+<DIR>
+<LI><A HREF="gperf.html#IDX35">in_word_set</A>
+<LI><A HREF="gperf.html#IDX40">Initializers</A>
+</DIR>
+<H2><A NAME="cindex_j">j</A></H2>
+<DIR>
+<LI><A HREF="gperf.html#IDX45">Jump value</A>
+</DIR>
+<H2><A NAME="cindex_k">k</A></H2>
+<DIR>
+<LI><A HREF="gperf.html#IDX6">Keywords section</A>
+</DIR>
+<H2><A NAME="cindex_m">m</A></H2>
+<DIR>
+<LI><A HREF="gperf.html#IDX3">Minimal perfect hash functions</A>
+</DIR>
+<H2><A NAME="cindex_n">n</A></H2>
+<DIR>
+<LI><A HREF="gperf.html#IDX37">NUL</A>
+</DIR>
+<H2><A NAME="cindex_s">s</A></H2>
+<DIR>
+<LI><A HREF="gperf.html#IDX39">Slot name</A>
+<LI><A HREF="gperf.html#IDX2">Static search structure</A>
+<LI><A HREF="gperf.html#IDX36"><CODE>switch</CODE></A>, <A HREF="gperf.html#IDX43"><CODE>switch</CODE></A>
+</DIR>
+
+
+<P><HR><P>
+This document was generated on 12 June 2003 using
+<A HREF="http://wwwinfo.cern.ch/dis/texi2html/">texi2html</A>&nbsp;1.56k.
+</BODY>
+</HTML>
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