%{
#include <stdio.h>
#include <string.h>
int verbose = 0;
char *progName = NULL;
char *filename = "-";
%}
%option noyywrap
%x FNAME
%%
^"-h"           |
^"-?"           |
^"--help"       { printf("usage is: %s [--help | -h | -?] ", progName);
                  printf("[--verbose | -v ...] ");
                  printf("[(--file | -f) filename]\n");
                  exit(0);
                }
^"-v"           |
^"--verbose"    { verbose++; }
^"-f"           |
^"--file"       { BEGIN FNAME;
                  filename = "";
                }
.*              { printf("unknown option '%s'!\n", yytext);
                  exit(1);
                }
<FNAME>.+       { filename = strdup(yytext); BEGIN INITIAL; }
%%
int main(int argc, char *argv[]) {
    progName = *argv;
    while(++argv,--argc) {
        yy_scan_string(*argv);
        yylex();
    }
    if(!filename || !*filename) {
        printf("No filename given with option --file!\n");
        exit(1);
    }
    printf("Now starting to frobnicate with:\n");
    printf("verbose = %d\n", verbose);
    printf("file = '%s'\n", filename);
}