YACC(1)                                                   YACC(1)

NAME
       Yacc - an LALR(1) parser generator

SYNOPSIS
       yacc  [  -dlrtv  ] [ -b file_prefix ] [ -p symbol_prefix ]
       filename

DESCRIPTION
       Yacc reads the grammar specification in the file  filename
       and generates an LR(1) parser for it.  The parsers consist
       of a set of LALR(1) parsing tables and  a  driver  routine
       written  in  the  C  programming  language.  Yacc normally
       writes the parse tables and the driver routine to the file
       y.tab.c.

       The following options are available:

              -b file_prefix
                     The  -b  option changes the prefix prepended
                     to the  output  file  names  to  the  string
                     denoted  by file_prefix.  The default prefix
                     is the character y.

              -d     The -d option causes the header file y.tab.h
                     to be written.

              -l     If the -l option is not specified, yacc will
                     insert #line  directives  in  the  generated
                     code.   The  #line directives let the C com-
                     piler relate errors in the generated code to
                     the  user's original code.  If the -l option
                     is specified, yacc will not insert the #line
                     directives.   #line  directives specified by
                     the user will be retained.

              -p symbol_prefix
                     The -p option changes the  prefix  prepended
                     to  yacc-generated  symbols  to  the  string
                     denoted by symbol_prefix.  The default  pre-
                     fix is the string yy.

              -r     The  -r  option causes yacc to produce sepa-
                     rate files for code and  tables.   The  code
                     file  is named y.code.c, and the tables file
                     is named y.tab.c.

              -t     The  -t  option  changes  the   preprocessor
                     directives  generated by yacc so that debug-
                     ging statements will be incorporated in  the
                     compiled code.

              -v     The   -v   option  causes  a  human-readable
                     description of the generated  parser  to  be
                     written to the file y.output.

       If  the  environment  variable  TMPDIR  is set, the string
       denoted by TMPDIR will be used as the name of  the  direc-
       tory where the temporary files are created.

FILES
       y.code.c
       y.tab.c
       y.tab.h
       y.output
       /tmp/yacc.aXXXXXX
       /tmp/yacc.tXXXXXX
       /tmp/yacc.uXXXXXX

DIAGNOSTICS
       If  there  are rules that are never reduced, the number of
       such rules is reported on standard error.   If  there  are
       any LALR(1) conflicts, the number of conflicts is reported
       on standard error.

                          July 15, 1990                         1