levy@ttrdc.UUCP (Daniel R. Levy) (03/18/89)
Unix-Gurus of the net, HALLLLLLLLLLP!!!! I have made the apparent mistake of believing the SUN manpage rmt(8C) for /etc/rmt, the remote magtape daemon. According to the documentation, as I read it, I should be able to start /etc/rmt and feed it commands and data, and expect acknowledgments and data back from it. Well, that doesn't seem to work very well (read: at ALL). I tried it locally (that shouldn't matter, should it?) and here's what happens with a tape, write protect turned off (i.e. writeable), in drive /dev/rst0, on a SUN4 under SunOS 4.0: skfe$ ls -l /dev/rst0 crw-rw-rw- 1 root 18, 0 Aug 31 1988 /dev/rst0 skfe$ echo TEST | dd conv=sync of=/dev/rst0 0+1 records in 1+0 records out skfe$ dd if=/dev/rst0 TEST 1+0 records in 1+0 records out skfe$ /etc/rmt O /dev/rst0 438 [me -- note that 438 decimal is 0666 octal] R 512 [me -- try to read a record] E2 [from /etc/rmt] No such file or directory [from /etc/rmt] S [me -- try to get tape status] E9 [from /etc/rmt] Bad file number [from /etc/rmt] skfe$ echo $? 3 The manpage doesn't say what input commands are supposed to be terminated with; I am assuming newline since the returned acknowledgment/error commands are also thus terminated. I tried null, and then I tried space, instead; neither elicited any output from /etc/rmt at all. I get the same behavior on a Sun-3 under SunOS 3.5 as I did above. At this point I'm up a (binary) tree. Does /etc/rmt really WORK, and what should I send it to make it work? Does it require arguments? (I found that if I gave it an argument, it would create an empty file of the same name as the argument -- weird?!?) Thanks mucho in advance-o! -- Daniel R. Levy UNIX(R) mail: att!ttbcad!levy AT&T Bell Laboratories 5555 West Touhy Avenue Any opinions expressed in the message above are Skokie, Illinois 60077 mine, and not necessarily AT&T's.
guy@auspex.UUCP (Guy Harris) (03/22/89)
Oh, BTW:
>O /dev/rst0 438 [me -- note that 438 decimal is 0666 octal]
Note also that the "mode" argument to the "O" command is an *open* mode,
not a file permissions mode - the description says "open the specified
device using the indicated mode", which pertains better to open modes
such as O_RDONLY, etc. than to file-creation modes - so it should be
something like 0 (O_RDONLY), 1 (O_WRONLY), or 2 (O_RDWR), rather than
something like 0666.
(Also, note that it's "Sun", not "SUN" - it's an acronym when it refers to
the Stanford University Network project, but not when it refers to Sun
Microsystems.)dcornutt@uahcs1.UUCP (David C. Cornutt) (03/29/89)
In article <3274@ttrdc.UUCP>, levy@ttrdc.UUCP (Daniel R. Levy) writes: > I have made the apparent mistake of believing the SUN manpage rmt(8C) for > /etc/rmt, the remote magtape daemon. According to the documentation, as I > read it, I should be able to start /etc/rmt and feed it commands and data, and > expect acknowledgments and data back from it. Well, that doesn't seem to work > very well (read: at ALL). I tried it locally (that shouldn't matter, should > it?) and here's what happens with a tape, write protect turned off (i.e. > writeable), in drive /dev/rst0, on a SUN4 under SunOS 4.0: > > O /dev/rst0 438 [me -- note that 438 decimal is 0666 octal] ^^^^^^^^^ ^^^ > Daniel R. Levy UNIX(R) mail: att!ttbcad!levy I went through this same exercise about a year ago. If I remember right (which I frequently don't), you have to put each of the arguments to every command on a line by itself; i.e., separate the command args with newlines instead of spaces. Sorry about not having a signature or return path. I just got back on the net after a long absence, and I haven't learned the local topology yet. David Cornutt uahcs1