dosemu and CLIPPER locks (again)

[Anderson Pereira Ataides <anderson.pa@persogo.com.br>]

Hi all,

Ok it's a boring thing, but I have to tell you some experience I had with 
this issue.

dosem insists in not seeing Windows locks. Note that dosemu is accessing dbf 
file in local Linux filesystem and Windows can not see dosemu file locks. The 
problem still occurs between two Linux workstation one accessing locally an 
other via NFS.

A friend (from this list) suggested me access dbf via smbmounted volume. I 
decided to try it and bingo. It worked but I noticed something wrong. Using 
DBU I opened a dbf file in dosem and Windows "recognized" locked file and 
gave me a warning and did nod display file (that was expected). When I opened 
a file in Windows, the DBU (in dosemu) displayed an error message (Corruption 
detected) and aborted.

I tried to hack mfs.c an saw some comments about locking. My conclusion is 
that this problem will not be solved between windows and Linux, because they 
do not "speak" same language when topic is locking. I saw there is a piece of 
code extracted from samba source an comment was "I don't know why it's 
there... Someone is playing games with lock/unlock". So I thought: samba team 
probably have problem too. How do they solve this problem? Do they cope with 
locks keeping track of locks themselves instead of locking linux filesystem?

Unhappy with this situation I tried to use FlagShip (a language similar to 
CLIPPER). Their documentation says that dbf files can not be accessed 
simultaneously from Windows (DOS) and Linux because of locking issues. I 
ignored this comment and compíled a piece of program and result was the same 
that in dosemu: Windows files did not see FlagShip locks.

Do you think we can solve it?

Hope my comments can help dosemu development team.

Ooops! Almost forgot to tell you my configuration:
	Conectiva Linux 7.0
	kernel 2.4.18	(compiled myself)
	dosemu 1.1.4.9	(compiled myself)
	samba 2.2.7a	(compiled myself)
	MS-DOS 7 (win98)

[]s
Anderson Pereira Ataides
-
To unsubscribe from this list: send the line "unsubscribe linux-msdos" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html