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57 lines
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<!-- This HTML file has been created by texi2html 1.51
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from gperf.texi on 7 May 2003 -->
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<TITLE>Perfect Hash Function Generator - 5 Known Bugs and Limitations with gperf</TITLE>
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</HEAD>
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<BODY>
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Go to the <A HREF="gperf_1.html">first</A>, <A HREF="gperf_6.html">previous</A>, <A HREF="gperf_8.html">next</A>, <A HREF="gperf_10.html">last</A> section, <A HREF="gperf_toc.html">table of contents</A>.
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<P><HR><P>
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<H1><A NAME="SEC25" HREF="gperf_toc.html#TOC25">5 Known Bugs and Limitations with <CODE>gperf</CODE></A></H1>
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<P>
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The following are some limitations with the current release of
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<CODE>gperf</CODE>:
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</P>
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<UL>
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<LI>
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The <CODE>gperf</CODE> utility is tuned to execute quickly, and works quickly
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for small to medium size data sets (around 1000 keywords). It is
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extremely useful for maintaining perfect hash functions for compiler
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keyword sets. Several recent enhancements now enable <CODE>gperf</CODE> to
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work efficiently on much larger keyword sets (over 15,000 keywords).
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When processing large keyword sets it helps greatly to have over 8 megs
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of RAM.
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<LI>
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The size of the generate static keyword array can get <EM>extremely</EM>
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large if the input keyword file is large or if the keywords are quite
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similar. This tends to slow down the compilation of the generated C
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code, and <EM>greatly</EM> inflates the object code size. If this
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situation occurs, consider using the <SAMP>`-S'</SAMP> option to reduce data
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size, potentially increasing keyword recognition time a negligible
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amount. Since many C compilers cannot correctly generate code for
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large switch statements it is important to qualify the <VAR>-S</VAR> option
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with an appropriate numerical argument that controls the number of
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switch statements generated.
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<LI>
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The maximum number of selected byte positions has an
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arbitrary limit of 255. This restriction should be removed, and if
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anyone considers this a problem write me and let me know so I can remove
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the constraint.
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</UL>
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<P><HR><P>
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Go to the <A HREF="gperf_1.html">first</A>, <A HREF="gperf_6.html">previous</A>, <A HREF="gperf_8.html">next</A>, <A HREF="gperf_10.html">last</A> section, <A HREF="gperf_toc.html">table of contents</A>.
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</BODY>
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</HTML>
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