cclose instead of fclose
cgetc instead of fgetc
cputc instead of fputc

scanf instead of fscanf

int instead of short

must use cc test.c -lp to use iolib functions

srand() is different, see example
rand() is available

no strcat (include as additional function definition)

fopen is available but I used copen instead
getchar() and putchar are available
fclose is missing, use cclose instead

open 0 = read
     1 = write
     2 = append

unirubik for v7 uses fputc to output and fgetc to input
unirubik for v6 uses cputc to output and cgetc to input

For v7:

	fp_in = fopen (fn_in, "r");
        if (fp_in == NULL)
        {
                printf ("No input file %s\n", fn_in);
                goto out;
        }
For v6:
        fp_in = copen (fn_in, 'r');
        if (fp_in < 0)
        {
                printf ("No input file %s\n", fn_in);
                goto out;
        }

For v7:

	srand (time(NULL));
	c = rand() % SIDES;
For v6:

	time(stime);
        srand(stime[1]);
	c = rand() % SIDES;

For v7:
	q[z][x][y] = fgetc(fp_in);
For v6:
 	q[z][x][y] = cgetc(fp_in);

For v7:
	FILE *output;
	fputc (q[z][x][y], output);
For v6:
	int output;
	cputc (q[z][x][y], output);


strcat function must be explicitly defined in v6 
strcat function is part of stdio in v7