yacc(1) 맨 페이지 - 윈디하나의 솔라나라

개요

섹션
맨 페이지 이름
검색(S)

yacc(1)

yacc(1)                          User Commands                         yacc(1)



NAME
       yacc - yet another compiler-compiler

SYNOPSIS
       yacc [-dltVv] [-b file_prefix] [-Q [y | n]]
             [-P parser] [-p sym_prefix] file


DESCRIPTION
       The  yacc  command converts a context-free grammar into a set of tables
       for a simple automaton that executes an LALR(1) parsing algorithm.  The
       grammar  can be ambiguous. Specified precedence rules are used to break
       ambiguities.


       The output file, y.tab.c, must be compiled by the C compiler to produce
       a function yyparse(). This program must be loaded with the lexical ana‐
       lyzer program, yylex(), as well as main() and yyerror(), an error  han‐
       dling  routine. These routines must be supplied by the user. The lex(1)
       command is useful for creating lexical analyzers usable by yacc.

OPTIONS
       The following options are supported:

       -b file_prefix    Uses file_prefix instead of y as the prefix  for  all
                         output  files. The code file y.tab.c, the header file
                         y.tab.h (created  when  -d  is  specified),  and  the
                         description  file y.output (created when -v is speci‐
                         fied), is  changed  to  file_prefix.tab.c,  file_pre‐
                         fix.tab.h, and file_prefix.output, respectively.


       -d                Generates  the  file  y.tab.h with the #define state‐
                         ments that associate the  yacc  user-assigned  "token
                         codes"  with  the  user-declared  "token names". This
                         association allows source files other than y.tab.c to
                         access the token codes.


       -l                Specifies  that the code produced in y.tab.c does not
                         contain any #line constructs. This option should only
                         be  used after the grammar and the associated actions
                         are fully debugged.


       -p sym_prefix     Uses sym_prefix instead of yy as the prefix  for  all
                         external  names  produced by yacc. The names affected
                         include the functions yyparse(),  yylex()  and  yyer‐
                         ror(),  and the variables yylval, yychar and yydebug.
                         (In the remainder of this section,  the  six  symbols
                         cited  are  referenced using their default names only
                         as a notational convenience.) Local names can also be
                         affected  by  the  -p  option. However, the -p option
                         does not affect #define symbols generated by yacc.


       -P parser         Allows you to  specify  the  parser  of  your  choice
                         instead  of  /usr/share/lib/ccs/yaccpar. For example,
                         you can specify:

                           example% yacc -P ~/myparser parser.y




       -Q[y|n]           The -Qy option puts the version stamping  information
                         in  y.tab.c.  This allows you to know what version of
                         yacc built the file. The  -Qn  option  (the  default)
                         writes no version information.


       -t                Compiles  runtime  debugging code by default. Runtime
                         debugging code is always generated in  y.tab.c  under
                         conditional  compilation  control.  By  default, this
                         code  is  not  included  when  y.tab.c  is  compiled.
                         Whether  or  not  the  -t option is used, the runtime
                         debugging code is under the control of  YYDEBUG  ,  a
                         preprocessor symbol. If YYDEBUG has a non-zero value,
                         then the debugging code is included. If its value  is
                         0, then the code is not included. The size and execu‐
                         tion time of a program produced without  the  runtime
                         debugging code is smaller and slightly faster.


       -v                Prepares the file y.output, which contains a descrip‐
                         tion of the parsing tables and a report on  conflicts
                         generated by ambiguities in the grammar.


       -V                Prints  on  the  standard  error  output  the version
                         information for yacc.


OPERANDS
       The following operand is required:

       file    A path name of a  file  containing  instructions  for  which  a
               parser is to be created.


EXAMPLES
       Example 1 Accessing the yacc Library


       Access  to the yacc library is obtained with library search operands to
       cc. To use the yacc library main:


         example% cc y.tab.c -ly




       Both the lex library and the yacc library contain main. To  access  the
       yacc main:


         example% cc y.tab.c lex.yy.c -ly -ll




       This  ensures that the yacc library is searched first, so that its main
       is used.



       The historical yacc libraries have contained two simple functions  that
       are  normally  coded by the application programmer. These library func‐
       tions are similar to the following code:


         #include <locale.h>
         int main(void)
         {
                 extern int yyparse();

                 setlocale(LC_ALL, "");

                 /* If the following parser is one created by lex, the
                    application must be careful to ensure that LC_CTYPE
                    and LC_COLLATE are set to the POSIX locale.  */
                 (void) yyparse();
                 return (0);
         }

         #include <stdio.h>

         int yyerror(const char *msg)
         {
                 (void) fprintf(stderr, "%s\n", msg);
                 return (0);
         }


ENVIRONMENT VARIABLES
       See environ(5) for descriptions of the following environment  variables
       that affect the execution of yacc: LANG, LC_ALL, LC_CTYPE, LC_MESSAGES,
       and NLSPATH.


       yacc can handle characters from EUC primary and supplementary  codesets
       as  one-token  symbols.  EUC  codes can only be single character quoted
       terminal symbols. yacc expects  yylex()  to  return  a  wide  character
       (wchar_t) value for these one-token symbols.

EXIT STATUS
       The following exit values are returned:

       0     Successful completion.


       >0    An error occurred.


FILES
       y.output      state transitions of the generated parser


       y.tab.c       source code of the generated parser


       y.tab.h       header file for the generated parser


       yacc.acts     temporary file


       yacc.debug    temporary file


       yacc.tmp      temporary file


       yaccpar       parser prototype for C programs


ATTRIBUTES
       See attributes(5) for descriptions of the following attributes:




       tab()   box;   cw(2.75i)  |cw(2.75i)  lw(2.75i)  |lw(2.75i)  ATTRIBUTE
       TYPEATTRIBUTE VALUE _  Availabilitydeveloper/base-developer-utilities
       _ Interface StabilityCommitted _ StandardSee standards(5).


SEE ALSO
       lex(1), attributes(5), environ(5), standards(5)

DIAGNOSTICS
       The  number  of reduce-reduce and shift-reduce conflicts is reported on
       the standard error output. A more  detailed  report  is  found  in  the
       y.output  file.  Similarly,  if  some  rules are not reachable from the
       start symbol, this instance is also reported.

NOTES
       Because file names are fixed, at most one yacc process can be active in
       a given directory at a given time.


       Users are encouraged to avoid using $ as part of any identifier name.



SunOS 5.11                        8 Jun 2011                           yacc(1)
맨 페이지 내용의 저작권은 맨 페이지 작성자에게 있습니다.
RSS ATOM XHTML 5 CSS3