YACC(1)YACC(1)NAMEyacc - an LALR(1) parser generator
SYNOPSISyacc [ -dlrtv ] [ -b file_prefix ] [ -p symbol_prefix ] filename
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) pars‐
ing tables and a driver routine written in the C programming language.
Yacc normally writes the parse tables and the driver routine to the
The following options are available:
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 writ‐
-l If the -l option is not specified, yacc will insert #line
directives in the generated code. The #line directives
let the C compiler 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. Any #line
directives specified by the user will be retained.
The -p option changes the prefix prepended to yacc-gener‐
ated symbols to the string denoted by symbol_prefix. The
default prefix is the string yy.
-r The -r option causes yacc to produce separate 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 gener‐
ated by yacc so that debugging statements will be incor‐
porated 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 directory where the temporary files are
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.
4.3 Berkeley Distribution May 24, 1993 YACC(1)