1: /* @(#)yyless.c 4.2 1/9/85 */ 2: 3: yyless(x) 4: { 5: extern char yytext[]; 6: register char *lastch, *ptr; 7: extern int yyleng; 8: extern int yyprevious; 9: lastch = yytext+yyleng; 10: if (x>=0 && x <= yyleng) 11: ptr = x + yytext; 12: else 13: ptr = (char *) x; 14: while (lastch > ptr) 15: yyunput(*--lastch); 16: *lastch = 0; 17: if (ptr >yytext) 18: yyprevious = *--lastch; 19: yyleng = ptr-yytext; 20: }