[Oberon] problem in attempt to write a FAT file

[Peter Easthope]

Oberoners,

Can anyone explain this phenomenon in PC Native 
23.06.2002 and 24.08.2002 running on an old 486 
DX?  If there is no explanation at hand, can anyone
replicate it at least?

The FAT file system is mounted with this statement 
in Oberon.Text.

		{ FileSystem.Mount C       FatFS IDE0#01 ~ }

Successive attempts to write a DOS file alternately
fail and work with the following trap.  

Regards,       Peter E.

TRAP -14  NIL reference ( 00000000H ) (PC Native 24.08.2002)
OFSFATVolumes.AssignDirectoryEntry  PC = 22430
	c =  00000000H
	dc =  00000000H
	direntry =  00000010H
	dummy = 0
	num = 0
	p =  00396180H
	pos = 0
	res = 0
	vol =  001B0AE0H
OFSFATVolumes.WriteDirectoryEntry  PC = 24156
	@dim = 2048
	chksum =  00000000X
	cluster = 0
	d = 0
	dirCache =  00000000H
	direntry =  00000010H
	dummy = 0
	idx = 0
	k = 0
	n = 0
	pos = 0
	res = 0
	t = 0
	unicode = 107, 101, 114, 109, 105, 116, 47, 109 ...
	vol =  001B0AE0H
OFSFATFiles.Rename  PC = 2703
	d = 52542
	f =  0033EE60H
	fn = "mailout.Bak"
	fs =  00302500H
	i = 18
	new = "kermit/mailout.Bak"
	newf =  00000000H
	newpath = "kermit/"
	old = "kermit/mailout"
	oldpath = "kermit/"
	rep =  00000000H
	res = 0
	t = 26142
OFS.Rename  PC = 4610
	fnew = "kermit/mailout.Bak"
	fold = "kermit/mailout"
	new = "C:kermit/mailout.Bak"
	nfs =  00302500H
	ofs =  00302500H
	old = "C:kermit/mailout"
	pnew = "C"
	pold = "C"
	res = 0
Files.Rename  PC = 1946
	new = "C:kermit/mailout.Bak"
	old = "C:kermit/mailout"
	res = 0
ET.RenameOld  PC = 13951
	bck = "C:kermit/mailout.Bak"
	i = 20
	name = "C:kermit/mailout"
	res = 0
ET.store  PC = 14607
	R =  00000034H
	S =  00000030H
	V =  00000000H
	ch =  00000000X
	f =  00000000H
	len = 0
	par =  001A6240H
	r =  00000028H
	tF =  0019D5E0H
	typ = a
ET.StoreAscii  PC = 15024
Oberon.Call  PC = 4847
	Mod =  00066880H
	P = ET.StoreAscii  PC = 15014
	i = 3
	j = 13
	name = "StoreAscii"
	new = FALSE
	par =  001A6240H
	res = 1
TextFrames.CallCmd  PC = 12014
	F =  003051E0H
	cmd = "ET.StoreAscii"
	new = FALSE
	par =  001A6240H
	pos = 80
	res = 1
TextFrames.Call  PC = 12902
	F =  003051E0H
	S =  00000048H
	h = 0
	hint = "ET.tem."
	i = -1
	new = FALSE
	pos = 69
TextFrames.Edit  PC = 20124
	F =  003051E0H
	Keys = {1}
	M =  00000060H
	R =  0000004CH
	X = 387
	Y = 595
	beg = 0
	buf =  00000000H
	ch =  00000000X
	end = 0
	keysum = {1}
	pos = 69
	text =  00000000H
	time = 0
TextFrames.Handle  PC = 21209
	F =  003051E0H
	F1 =  00000000H
	M =  00000020H
ET.Handle  PC = 10006
	F =  003051E0H
	M =  0000000CH
	T =  0033B120H
	handled = FALSE
	ml = FALSE
	tF =  003051E0H
MenuViewers.Handle  PC = 4432
	M =  00000014H
	Main =  0019D5E0H
	Menu =  003051E0H
	V =  0019D680H
	V1 =  00000000H
Oberon.Loop  PC = 8548
	M =  00000010H
	N =  0000000CH
	V =  0019D680H
	X = 387
	Y = 595
	ch =  00000020X
	keys = {1}
	oldshift = {}
	shift = {}
System.Init  PC = 20160
	F =  0030B5A0H
	S =  00000044H
	T =  0030B520H
	Wt =  00000050H
	ok = FALSE
OFSBoot.Call  PC = 413
	c = System.Init  PC = 19636
	cmd = "Init"
	i = 11
	j = 4
	m =  00163440H
	protect = TRUE
OFSBoot.BootSystem  PC = 2754
	s = "System.Init"
OFSBoot.$$  PC = 13
	@SELF =  0003F1C0H
	SELF =  0003F1C0H
 
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