I have an sm/ directory, but I've deleted its logfiles.
I got this walkback.
Looks like the existence of the directory is not really enough...
And openLogFileReadOnly can return nil, which isn't being checked for.

22 July 2003 1:56:09 pm

VM: unix - Squeak3.4 of 1 March 2003 [latest update: #5170]
Image: Squeak3.6beta [latest update: #5371]

UndefinedObject(Object)>>doesNotUnderstand: #setToEnd
	Receiver: nil
	Arguments and temporary variables: 
		aMessage: 	a Message with selector: #setToEnd and arguments: #()
	Receiver's instance variables: 
nil

[] in SMSqueakMap>>lastTransactionInLog
	Arguments and temporary variables: 
		file: 	nil
		key: 	nil

BlockContext>>ensure:
	Receiver: [] in SMSqueakMap>>lastTransactionInLog
	Arguments and temporary variables: 
		aBlock: 	[] in SMSqueakMap>>lastTransactionInLog
		returnValue: 	nil
	Receiver's instance variables: 
		sender: 	BlockContext>>ensure:
		pc: 	53
		stackp: 	0
		nargs: 	0
		startpc: 	50
		home: 	SMSqueakMap>>lastTransactionInLog

SMSqueakMap>>lastTransactionInLog
	Receiver: a SMSqueakMap
	Arguments and temporary variables: 
		file: 	nil
		key: 	nil
	Receiver's instance variables: 
		cards: 	a Dictionary(an
UUID('017b1882-9376-4bf7-b128-37418b1a5bbc')->SMCard[Met...etc...
		categories: 	a Dictionary(an
UUID('0990c683-1a6e-4452-98b4-f17ded06a3c9')->SMCat...etc...
		repositories: 	a Dictionary(an
UUID('2bbc04df-fc80-476d-9caa-6877fa938bc2')->a S...etc...
		dir: 	'sm'
		transactionCounter: 	2139
		firstTransactionNumber: 	2139
		daysBacklog: 	182
		adminPassword: 	nil
		module: 	nil
		installedPackages: 	a Dictionary(an
UUID('047a3b12-7e52-4c5d-be8b-d06635fc4f1c')...etc...
		installCounter: 	28


--- The full stack ---
UndefinedObject(Object)>>doesNotUnderstand: #setToEnd
[] in SMSqueakMap>>lastTransactionInLog
BlockContext>>ensure:
SMSqueakMap>>lastTransactionInLog
 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
SMSqueakMap>>updatesSinceTransactionInLog:
SMSqueakMap>>synchWithLog
SMSqueakMap>>loadUpdatesFull:
SMSqueakMap>>loadFull
UndefinedObject>>DoIt
Compiler>>evaluate:in:to:notifying:ifFail:
[] in TextMorphEditor(ParagraphEditor)>>evaluateSelection
BlockContext>>on:do:
TextMorphEditor(ParagraphEditor)>>evaluateSelection
TextMorphEditor(ParagraphEditor)>>doIt
[] in TextMorphEditor(ParagraphEditor)>>doIt:
TextMorphEditor(Controller)>>terminateAndInitializeAround:
TextMorphEditor(ParagraphEditor)>>doIt:
TextMorphEditor(ParagraphEditor)>>dispatchOnCharacter:with:
TextMorphEditor>>dispatchOnCharacter:with:
TextMorphEditor(ParagraphEditor)>>readKeyboard
TextMorphEditor>>readKeyboard
[] in TextMorphForEditView(TextMorph)>>keyStroke:
TextMorphForEditView(TextMorph)>>handleInteraction:fromEvent:
TextMorphForEditView>>handleInteraction:fromEvent:
TextMorphForEditView(TextMorph)>>keyStroke:
TextMorphForEditView>>keyStroke:
TextMorphForEditView(TextMorph)>>handleKeystroke:
KeyboardEvent>>sentTo:
TextMorphForEditView(Morph)>>handleEvent:
TextMorphForEditView(Morph)>>handleFocusEvent:
[] in HandMorph>>sendFocusEvent:to:clear:
PasteUpMorph>>becomeActiveDuring:
HandMorph>>sendFocusEvent:to:clear:
HandMorph>>sendEvent:focus:clear:
HandMorph>>sendKeyboardEvent:
HandMorph>>handleEvent:
HandMorph>>processEvents
[] in WorldState>>doOneCycleNowFor:
Array(SequenceableCollection)>>do:
WorldState>>handsDo:
WorldState>>doOneCycleNowFor:
WorldState>>doOneCycleFor:
PasteUpMorph>>doOneCycle
[] in Project class>>spawnNewProcess
[] in BlockContext>>newProcess