With the simple unified diff below, I get the following results on
the other drive.  Note EINVAL instead of EIO.  Drive quirk?

	Sean.

sean# ./tstdvd -noread
lseek(3, 0, 0) -> 0
lseek(3, 2048, 0) -> 2048
lseek(3, 0, 2) -> 0
lseek(3, 2496425984, 0) -> 2496425984
lseek(3, 0, 1) -> 2496425984
lseek(3, 4096, 1) -> 2496430080
lseek(3, 0, 1) -> 2496430080
lseek(3, 697884672, 0) -> 697884672
lseek(3, 0, 1) -> 697884672
lseek(3, 0, 2) -> 0
lseek(3, 0, 1) -> 0
lseek(3, 8192, 0) -> 8192
lseek(3, 0, 1) -> 8192

sean# ./tstdvd
lseek(3, 0, 0) -> 0
block read OK
lseek(3, 2048, 0) -> 2048
block read OK
lseek(3, 0, 2) -> 0
block read OK
lseek(3, 2496425984, 0) -> 2496425984
block read OK
lseek(3, 0, 1) -> 2496428032
block read OK
lseek(3, 4096, 1) -> 2496434176
errno = 0  read failed: Invalid argument
errno = 22 doing lseek: Invalid argument
errno = 22 doing lseek: Invalid argument
errno = 22 doing lseek: Invalid argument
errno = 22 doing lseek: Invalid argument
errno = 22 doing lseek: Invalid argument
errno = 22 doing lseek: Invalid argument
errno = 22 doing lseek: Invalid argument

ahc0: target 2 synchronous at 10.0MHz, offset = 0xf
cd1(ahc0:2:0):  Check Condition on CDB: 0x08 12 99 92 01 00
    SENSE KEY:  Illegal Request
   INFO FIELD:  1218960
     ASC/ASCQ:  Logical Block Address Out of Range

sean# diff -u ../tstcd.c tstdvd.c
--- ../tstcd.c  Thu Aug 24 21:02:58 2000
+++ tstdvd.c    Thu Aug 24 21:05:07 2000
@@ -4,7 +4,7 @@
 #include <fcntl.h>
 #include <errno.h>
 
-char cd_device[] = "/dev/rcd0d";
+char cd_device[] = "/dev/rcd1d";
 
 void test_lseek(int, off_t, int);
 void read_a_block(int);
@@ -36,24 +36,24 @@
   test_lseek(fd, (off_t)     0L, SEEK_END);
 
   /* from the disklabel:
-     total sectors: 296118
+     total sectors: 1218960 
      bytes/sector: 2048
   */
   /* seek to end but one sector, print where we are */
-  test_lseek(fd, (off_t)   2048L * 296116L, SEEK_SET);
-  test_lseek(fd, (off_t)                0L, SEEK_CUR);
+  test_lseek(fd, (off_t)   2048L * 1218958L, SEEK_SET);
+  test_lseek(fd, (off_t)                 0L, SEEK_CUR);
 
   /* seek two forward, print where we are - shouldn't be able to do this */
   test_lseek(fd, (off_t)      2L *   2048L, SEEK_CUR);
   test_lseek(fd, (off_t)                0L, SEEK_CUR);
 
   /* seek waaaaaay past the end, print where we are - shouldn't be able to do this */
-  test_lseek(fd, (off_t) 2L * 2048L * 296116L, SEEK_SET);
-  test_lseek(fd, (off_t)                  0L, SEEK_CUR);
+  test_lseek(fd, (off_t) 2L * 2048L * 1218958L, SEEK_SET);
+  test_lseek(fd, (off_t)                   0L, SEEK_CUR);
 
   /* try again at end, print where we are */
   test_lseek(fd, (off_t) 0L, SEEK_END);
-  test_lseek(fd, (off_t)           0L, SEEK_CUR);
+  test_lseek(fd, (off_t) 0L, SEEK_CUR);
 
   /* try again at block 4, print where we are */
   test_lseek(fd, (off_t) 4L *   2048L, SEEK_SET);