#include <stdio.h>
#include <fcntl.h>

#include <sys/types.h>
#include <unistd.h>

extern char * malloc();

#define BLOCK_SIZE	(512 * 64)

int main( argc, argv)
	int		argc;
	char	** argv;
{
	long	start;

	int 	len,
			fd,
			stuff_read;
	
	char	* device_name,
			* buf;
	
	char	command[ 80];

	if( argv[ 1])
	{
		device_name = argv[ 1];
	}
	else
	{
		fprintf( stderr, "usage: %s <file>\n", argv[ 0]);
		exit( 1);
	}

	if( !(buf = malloc( BLOCK_SIZE)))
	{
		fprintf( stderr, "%s: ", argv[ 0]);
		perror( device_name);
		exit( 1);
	}

	if( (fd = open( device_name, O_RDONLY)) < 0)
	{
		fprintf( stderr, "%s: ", argv[ 0]);
		perror( device_name);
		exit( 1);
	}

	while( fgets( command, 80, stdin))
	{
		sscanf( command, "%ld %d", &start, &len);

		if( lseek( fd, start, SEEK_SET) < 0)
		{
			fprintf( stderr, "%s: ", argv[ 0]);
			perror( device_name);
			exit( 1);
		}

		stuff_read = 0;

		while( stuff_read < len)
		{
			int		amount_to_read;

			amount_to_read = 
				((len - stuff_read) < BLOCK_SIZE) ?
					(len - stuff_read) :
					BLOCK_SIZE;

			if( read( fd, buf, amount_to_read) < 0)
			{
				fprintf( stderr, "%s: ", argv[ 0]);
				perror( device_name);
				exit( 1);
			}

			write( 1, buf, amount_to_read);

			stuff_read += amount_to_read;
		}
	}

	close( fd);

	return( 0);
}