main.c

#include "base_flex.h"
#include <ctype.h>
#include <err.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <unistd.h>

int main(int argc, char **argv) {
  struct stat s;
  char *buffer;
  int fd;
  fd = open(argv[1], O_RDONLY);
  if (fd < 0)
    return EXIT_FAILURE;
  fstat(fd, &s);
  /* PROT_READ disallows writing to buffer: will segv */
  buffer = mmap(0, s.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
  // read file ok -> then process with flex
  if (buffer != (void *)-1) {
    yybuffer buff1;                  // create a new buffer
    buff1 = S1__scan_string(buffer); // read string into buff1

    S1__switch_to_buffer(buff1); // switch to the new buffer
    S1_lex();                    // run the lexer defined in scanner.l
    S1__delete_buffer(buff1);    // delete the buffer
    munmap(buffer, s.st_size);   // unmap the file from memory
  }
  close(fd); // close file descriptor.
  return 0;
}