/* DREDGE ddu: nnnnnnn */
/* ddu: is a disk device.
   does a read logical NOT VIRTUAL block of block number nnnnnnnn
   outputs the block (8-bits-wide) to outfile
   nnn is long */
#define LUN 4
#define EFN 4
#define BLOCKSIZE 512
#include <cx.h>
#include <fit.h>
#include <qiofun.h>

char	buffer[BLOCKSIZE];

helpless()
{puts("usage\tDREDGE\tddu: nnnnnnnn outfilespec");
 puts("DEC RSX/VMS specific file (sc)raper.");
 puts("ddu: is device. nnnnnnnn is (decimal long) logical block number");
 puts("outfilespec is file to copy block to.");
 exit();
}

main(argc,argv)
int argc;
char **argv;
{
 FILE		*optr;
 int		i;
 int		dsw;
 int		prl[6];
 int		isb[2];
 int		devnam;
 int		devunt;
 long		lbn;
 if	(argc!=4)	helpless();
 if	(argv[1][3]!=':')	helpless();
 if	(!isdigit(argv[1][2]))	helpless();
 argv[1][0] = toupper(argv[1][0]);
 argv[1][1] = toupper(argv[1][1]);
 copy(&devnam,argv[1],2);
 devunt = argv[1][2] - '0';
 dsw = alun(LUN,devnam,devunt);
 if	(dsw!=IS_SUC)
	{error("Can't attach device! dsw=%oo devnam=%oo devunt=%oo",dsw,devnam,devunt);
	}
 ;
 sscanf(argv[2],"%ld",&lbn);
 prl[0] = buffer;
 prl[1] = BLOCKSIZE;
 prl[2] = 0;
 prl[3] = lbn>>16;
 prl[4] = lbn;
 prl[5] = 0;
 dsw = qiow(IO_RLB,LUN,EFN,isb,0,prl);
 if	(dsw!=IS_SUC)	error("dsw=%oo isb[0]=%oo isb[1]=%oo\n",dsw,isb[0],isb[1]);
 optr = fopen(argv[3],"wn");
 if	(!optr)	error("Can't open output file \"%s\"\n",argv[3]);
 fput(buffer,BLOCKSIZE,optr);
 fclose(optr);
}