The -r option has been implemented.  The -r option tells Yacc toput the read-only tables in y.tab.c and the code and variables iny.code.c.  Keith Bostic asked for this option so that :yyfix could beeliminated.     The -l and -t options have been implemented.  The -l option tellsYacc not to include #line directives in the code it produces.  The -toption causes debugging code to be included in the compiled parser.     The code for error recovery has been changed to implement the samealgorithm as AT&T Yacc.  There will still be differences in the wayerror recovery works because AT&T Yacc uses more default reductionsthan Berkeley Yacc.     The environment variable TMPDIR determines the directory wheretemporary files will be created.  If TMPDIR is defined, temporary fileswill be created in the directory whose pathname is the value of TMPDIR.By default, temporary files are created in /tmp.     The keywords are now case-insensitive.  For example, %nonassoc,%NONASSOC, %NonAssoc, and %nOnAsSoC are all equivalent.     Commas and semicolons that are not part of C code are treated ascommentary.     Line-end comments, as in BCPL, are permitted.  Line-end commentsbegin with // and end at the next end-of-line.  Line-end comments arepermitted in C code; they are converted to C comments on output.     The form of y.output files has been changed to look more likethose produced by AT&T Yacc.     A new kind of declaration has been added.  The form of the declarationis	  %ident stringwhere string is a sequence of characters begining with a double quoteand ending with either a double quote or the next end-of-line, whichevercomes first.  The declaration will cause a #ident directive to be writtennear the start of the output file.     If a parser has been compiled with debugging code, that code can beenabled by setting an environment variable.  If the environment variableYYDEBUG is set to 0, debugging output is suppressed.  If it is set to 1,debugging output is written to standard output.