(flex.info.gz) Code-Level And API Options

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 16.3 Code-Level And API Options
 ===============================
 
 `--ansi-definitions, `%option ansi-definitions''
      instruct flex to generate ANSI C99 definitions for functions.
      This option is enabled by default.  If `%option
      noansi-definitions' is specified, then the obsolete style is
      generated.
 
 `--ansi-prototypes, `%option ansi-prototypes''
      instructs flex to generate ANSI C99 prototypes for functions.
      This option is enabled by default.  If `noansi-prototypes' is
      specified, then prototypes will have empty parameter lists.
 
 `--bison-bridge, `%option bison-bridge''
      instructs flex to generate a C scanner that is meant to be called
      by a `GNU bison' parser. The scanner has minor API changes for
      `bison' compatibility. In particular, the declaration of `yylex'
      is modified to take an additional parameter, `yylval'.  
      Bison Bridge.
 
 `--bison-locations, `%option bison-locations''
      instruct flex that `GNU bison' `%locations' are being used.  This
      means `yylex' will be passed an additional parameter, `yylloc'.
      This option implies `%option bison-bridge'.   Bison Bridge.
 
 `-L, --noline, `%option noline''
      instructs `flex' not to generate `#line' directives.  Without this
      option, `flex' peppers the generated scanner with `#line'
      directives so error messages in the actions will be correctly
      located with respect to either the original `flex' input file (if
      the errors are due to code in the input file), or `lex.yy.c' (if
      the errors are `flex''s fault - you should report these sorts of
      errors to the email address given in  Reporting Bugs).
 
 `-R, --reentrant, `%option reentrant''
      instructs flex to generate a reentrant C scanner.  The generated
      scanner may safely be used in a multi-threaded environment. The
      API for a reentrant scanner is different than for a non-reentrant
      scanner  Reentrant).  Because of the API difference between
      reentrant and non-reentrant `flex' scanners, non-reentrant flex
      code must be modified before it is suitable for use with this
      option.  This option is not compatible with the `--c++' option.
 
      The option `--reentrant' does not affect the performance of the
      scanner.
 
 `-+, --c++, `%option c++''
      specifies that you want flex to generate a C++ scanner class.
       Cxx, for details.
 
 `--array, `%option array''
      specifies that you want yytext to be an array instead of a char*
 
 `--pointer, `%option pointer''
      specify that  `yytext' should be a `char *', not an array.  This
      default is `char *'.
 
 `-PPREFIX, --prefix=PREFIX, `%option prefix="PREFIX"''
      changes the default `yy' prefix used by `flex' for all
      globally-visible variable and function names to instead be
      `PREFIX'.  For example, `--prefix=foo' changes the name of
      `yytext' to `footext'.  It also changes the name of the default
      output file from `lex.yy.c' to `lex.foo.c'.  Here is a partial
      list of the names affected:
 
 
               yy_create_buffer
               yy_delete_buffer
               yy_flex_debug
               yy_init_buffer
               yy_flush_buffer
               yy_load_buffer_state
               yy_switch_to_buffer
               yyin
               yyleng
               yylex
               yylineno
               yyout
               yyrestart
               yytext
               yywrap
               yyalloc
               yyrealloc
               yyfree
 
      (If you are using a C++ scanner, then only `yywrap' and
      `yyFlexLexer' are affected.)  Within your scanner itself, you can
      still refer to the global variables and functions using either
      version of their name; but externally, they have the modified name.
 
      This option lets you easily link together multiple `flex' programs
      into the same executable.  Note, though, that using this option
      also renames `yywrap()', so you now _must_ either provide your own
      (appropriately-named) version of the routine for your scanner, or
      use `%option noyywrap', as linking with `-lfl' no longer provides
      one for you by default.
 
 `--main, `%option main''
      directs flex to provide a default `main()' program for the
      scanner, which simply calls `yylex()'.  This option implies
      `noyywrap' (see below).
 
 `--nounistd, `%option nounistd''
      suppresses inclusion of the non-ANSI header file `unistd.h'. This
      option is meant to target environments in which `unistd.h' does
      not exist. Be aware that certain options may cause flex to
      generate code that relies on functions normally found in
      `unistd.h', (e.g. `isatty()', `read()'.)  If you wish to use these
      functions, you will have to inform your compiler where to find
      them.   option-always-interactive.  option-read.
 
 `--yyclass=NAME, `%option yyclass="NAME"''
      only applies when generating a C++ scanner (the `--c++' option).
      It informs `flex' that you have derived `NAME' as a subclass of
      `yyFlexLexer', so `flex' will place your actions in the member
      function `foo::yylex()' instead of `yyFlexLexer::yylex()'.  It
      also generates a `yyFlexLexer::yylex()' member function that emits
      a run-time error (by invoking `yyFlexLexer::LexerError())' if
      called.   Cxx.
 
 

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(flex.info.gz) Scanner Options

(flex.info.gz) Options for Scanner Speed and Size