#include <fcntl.h>  /* open(2) close(2)                                      */
#include <stdio.h>  /* printf(3)                                             */
#include <stdlib.h> /* malloc(3)                                             */
#include <unistd.h> /* read(2)                                               */

/* function declarations                                                     */
void next(void)            ;
void expression(int level) ;
void program(void)         ;
int  eval(void)            ;

/* global variables                                                          */
int token;           /* current token                                        */
char *src, *old_src; /* pointer to source code string                        */
int poolsize;        /* default size of text/data/stack                      */
int line;            /* line number                                          */

void next(void) {
  token = *src++;
  return;
}

void expression(void) {
  /* do nothing */
}

void program(void) {
  next(); /* get next token */
  while ( token > 0 ) {
    printf("token is: %c\n", token);
    next();
  }
}

int eval(void) {
  return 0;
}

/* entry point                                                               */
int main(int argc, char **argv) {
  int i;
  int fd;

  argc--;
  argv++;

  /* initalize global variables */
  poolsize = 256 * 1024; /* arbitrary */
  line = 1;

  if ( 0 > (fd = open(*argv, 0)) ) {
    printf("could not open(%s, 0)\n", *argv);
    return 1;
  }

  if (NULL == (src = old_src = malloc(poolsize)) ) {
    printf("could not malloc(%d)\n", poolsize);
    return 1;
  }

  if ( 0 >= (i = read(fd, src, poolsize - 1)) ) {
    printf("read() returned %d\n", i);
    return 1;
  }

  src[i] = 0;
  close(fd);

  program();
  return eval();
}