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diff --git a/doc/gperf_6.html b/doc/gperf_6.html deleted file mode 100644 index 92743c6..0000000 --- a/doc/gperf_6.html +++ /dev/null @@ -1,502 +0,0 @@ -<HTML> -<HEAD> -<!-- This HTML file has been created by texi2html 1.52b - from gperf.texi on 20 December 2009 --> - -<META HTTP-EQUIV="content-type" CONTENT="text/html; charset=UTF-8"> -<TITLE>Perfect Hash Function Generator - 5 Invoking gperf</TITLE> -</HEAD> -<BODY> -Go to the <A HREF="gperf_1.html">first</A>, <A HREF="gperf_5.html">previous</A>, <A HREF="gperf_7.html">next</A>, <A HREF="gperf_10.html">last</A> section, <A HREF="gperf_toc.html">table of contents</A>. -<P><HR><P> - - -<H1><A NAME="SEC17" HREF="gperf_toc.html#TOC17">5 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. - -</P> - - - -<H2><A NAME="SEC18" HREF="gperf_toc.html#TOC18">5.1 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>. - -</P> - - -<H2><A NAME="SEC19" HREF="gperf_toc.html#TOC19">5.2 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_5.html#SEC9">4.1.1.2 Gperf Declarations</A>). - -</P> -<DL COMPACT> - -<DT><SAMP>‘-e <VAR>keyword-delimiter-list</VAR>’</SAMP> -<DD> -<DT><SAMP>‘--delimiters=<VAR>keyword-delimiter-list</VAR>’</SAMP> -<DD> -<A NAME="IDX40"></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="SEC20" HREF="gperf_toc.html#TOC20">5.3 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_5.html#SEC9">4.1.1.2 Gperf Declarations</A>). - -</P> -<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&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 ANSI-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="SEC21" HREF="gperf_toc.html#TOC21">5.4 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_5.html#SEC9">4.1.1.2 Gperf Declarations</A>). - -</P> -<DL COMPACT> - -<DT><SAMP>‘-K <VAR>slot-name</VAR>’</SAMP> -<DD> -<DT><SAMP>‘--slot-name=<VAR>slot-name</VAR>’</SAMP> -<DD> -<A NAME="IDX41"></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="IDX42"></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="IDX43"></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 >= 'A' && c <= '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_5.html#SEC15">4.3 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><jjc@ai.mit.edu></CODE>. - -<DT><SAMP>‘-I’</SAMP> -<DD> -<DT><SAMP>‘--includes’</SAMP> -<DD> -Include the necessary system include file, <CODE><string.h></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="IDX44"></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>‘--length-table-name=<VAR>length-table-array-name</VAR>’</SAMP> -<DD> -<A NAME="IDX45"></A> -Allows you to specify the name for the generated array containing the -length table. Default name is <SAMP>‘lengthtable’</SAMP>. This option permits the -use of two length 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="IDX46"></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="SEC22" HREF="gperf_toc.html#TOC22">5.5 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="IDX47"></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="IDX48"></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="SEC23" HREF="gperf_toc.html#TOC23">5.6 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> - -<P><HR><P> -Go to the <A HREF="gperf_1.html">first</A>, <A HREF="gperf_5.html">previous</A>, <A HREF="gperf_7.html">next</A>, <A HREF="gperf_10.html">last</A> section, <A HREF="gperf_toc.html">table of contents</A>. -</BODY> -</HTML> |