gfl@relay.eu.net (Gerhard Fleischanderl) (10/17/89)
When I tried to use a dbm database from Sun386i and Sun-3 (both running SunOS 4.0.1), I encountered a strange effect. If the dbm file is created on a Sun386i, I cannot read it from the Sun-3 (and vice versa) ! The dbm(3x) routines firstkey() and fetch() both report "bad block" and dump core, when they access a dbm file created on the other architecture. The respective ".pag" files, which are created by identical instructions, differ in their 10 leading bytes obeying to the following pattern: Byte | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | ---------|-----|-----|-----|-----|-----|-----|-----|-----|-----|------| Sun386i | A | B | C | D | E | F | G | H | I | J | Sun-3 | B | A | D | C | F | E | H | G | J | I | Maybe the difference in byte ordering on 68020 and 80386, resp., is the reason for this incompatibility. An interesting aspect is that dbm files created on a MicroVax (Ultrix 3.0) are identical to those from a Sun386i. My priority question is: How can I access a dbm file, which has been created on a Sun386i (== MicroVax), on a Sun-3? (I need this to run the news software in a heterogeneous network.) Any help will be appreciated. If I will receive anything interesting, I will summarize to the list. Gerhard Fleischanderl Institut fuer Angewandte Informatik, Technical University Vienna Paniglgasse 16, A-1040 Vienna, Austria e-mail: gfl@vexpert.uucp
henry@cs.utexas.edu (10/24/89)
>When I tried to use a dbm database from Sun386i and Sun-3 (both running >SunOS 4.0.1), I encountered a strange effect. If the dbm file is created >on a Sun386i, I cannot read it from the Sun-3 (and vice versa) ! The format of dbm databases is (a) undocumented, and (b) machine-specific. Short of reimplementing dbm, there is no general cure that I know of. It isn't necessarily just a byte-ordering problem; there is also the question of whether dbm's hash function is machine-dependent. >... (I need this to run the news software in a heterogeneous network.) I am exploring the possibility of fixing Jon Zeeff's "dbz", which is a partial dbm lookalike sufficient for news, to be byte-order-independent. Henry Spencer at U of Toronto Zoology uunet!attcan!utzoo!henry henry@zoo.toronto.edu