# include "far.h"

devsize (a)
	{
	char c;
	long low, high, midpoint;


	low = 0;
	high = K64;

	for (;;)
		{
		midpoint = (low + high) / 2;

		if (midpoint == low)
			break;

		if (seek (a, (int) midpoint, 3) >= 0 && read (a, &c, 1) == 1)
			{
			low = midpoint;
			}

		else
			{
			if (errno == ENXIO)	/* off the disk */
				{
				high = midpoint;
				}
			else		/* on the disk but unreadable */
				{
				perror (NULL);
				low = midpoint;
				}
			}
		}

	seek (a, 0, 0);	/* return the file offset to the beginning */

	if (high >= K64)
		high = K64 - 1;		/* max. size */

	return (int) high;
	}
	char *
save (a)
	char *a;
	{
	char *b;

	b = alloc (lenstr (a) + 1);

	cpystr (b, a, NULL);

	return b;
	}