same lin parse

 hi all

i am new in lex programming,i tried to find one token (i.e. "="),then change
value of after "="  
i succeed in find token one occurence in one line using  follwing code

=[^\n<>"]*	{
			
			printf ("\n token value is   %s\n",yytext);
			printf ("\nenter new value\n ");
			memset (chr,0x00,sizeof(chr));	
			memset (next_char,0x00,sizeof(next_char));
			next_char[0] = '=';
			next_char[1] = ' ';

				scanf("%s",chr);
				strcpy(yytext,"=");
				strcat(next_char,chr);
				fputs(next_char,yyout);
				
					
		} 


but problem  if one line contain more than one occurence of "="  in same line
it change only first occurence token
so please anybody suggest best regular expression to solve this problem