Debug

Debug Output

Wine consists of a lot of different modules and provides ways to control debug output for each of the modules independently. In order to enable or disable the debug output for one these debug channels, you need to set the WINEDEBUG environment variable while starting a program. The WINEDEBUG variable needs to be specified in the following format:

WINEDEBUG=[+process:][class]+channel,[-process:][class]-channel,...

You need to specify at least the channel for which you would like to change the debug level. This usually matches the name of a dll provided by Wine, but there are also exceptions (see list at the end of the page). If you want to see all debug messages from ntdll, you would use the following line:

WINEDEBUG=+ntdll wine test.exe

In order to suppress all messages by ntdll you would simply use '-' instead of '+':

WINEDEBUG=-ntdll wine test.exe

Besides turning off/on all debug messages, you can also control different classes of debug levels. The supported classes are:

• err (critical errors, turned ON by default)
• fixme (warnings about unimplemented features, turned ON by default)
• warn (non critical errors, turned OFF by default)
• trace (all functions calls, turned OFF by default)

In case you want to see all warnings from ntdll (additionally to errors and fixmes), you could use the following line:

WINEDEBUG=warn+ntdll wine test.exe

Wine Staging also provides a way to control the debug settings for each (child) process independently. This is especially useful if you want to debug a game which needs to be started by a launcher or programs like Uplay. The following line will disable the debug output for all programs for which the executable image filename does not match game.exe:

WINEDEBUG=-game.exe:-all wine launcher.exe

If you also want to turn on relay for the game, you can use the following command line:

WINEDEBUG=-game.exe:-all,+game.exe:+relay wine launcher.exe

Usually you would write the debug messages into a file as the output can get quite big depending on the enabled debug channels. Several hundred megabytes or multiple gigabytes are not unusual when +relay is enabled for example. Another problem you may encounter are overlapped debug messages when a program uses multiple threads or sub processes. You can prevent this by using the append mode in the following way:

WINEDEBUG=... wine game.exe >> debug.log 2>&1

Now you should know everything required to create proper debug logs.

Debug Channels

As mentioned earlier the possible debug channels usually match the name of the dlls provided by Wine, but there are also exceptions and special debug channels. Those special debug channels do not control a single module but affect all modules or all debug messages. The most important ones are:

• tid prints the thread id before all debug messages
• timestamp prints the timestamp in front of all debug messages
• relay prints all functions calls to wine dlls and their return values
• seh show more detailed information about exceptions

You should use +tid if you are debugging multiple threads or processes and it generally doesn't hurt to enable it all the time. If you are searching for a bug and don't have a clue what is going wrong, the +relay channel might be useful. It prints a lot of information about all regular function calls and will often also contain a hint where the problem might be, but you should be aware that calls to COM interfaces are not logged with this method. You will for example not be able to find an error in d3d9 interfaces this way.

The +seh channel prints information about exceptions like invalid memory accesses. You should always take a look at it if the application crashes, especially when the application catches the exception and shows it's own crash dialog.

You can find more information about this special debug channels in the WineHQ Wiki.

Here is a list with all debug channels supported by Wine Staging:

accel	acledit	aclui	actctx
activeds	actxprxy	adpcm	advapi
advpack	alsa	amstream	animate
appbar	apphelp	appwizcpl	asmshader
aspi	atl	atom	authz
avicap	avifile	avrt	bcrypt
bidi	bitblt	bitmap	browseui
button	bytecodewriter	cabinet	capi
cards	caret	cdrom	chain
class	clipboard	clipping	clusapi
combase	combo	comboex	comm
commctrl	commdlg	compstui	computername
comsvcs	connect	console	context
coreaudio	cred	credui	crtdll
crypt	cryptasn	cryptdlg	cryptdll
cryptext	cryptnet	cryptui	ctapi32
cursor	d2d	d3d	d3d10
d3d10core	d3d11	d3d8	d3d9
d3d_bytecode	d3dcompiler	d3d_constants	d3d_decl
d3d_draw	d3d_perf	d3drm	d3d_shader
d3d_surface	d3d_synchronous	d3d_texture	d3dx
d3dxof	d3dxof_dump	d3dxof_parsing	datetime
dbgeng	dbghelp	dbghelp_coff	dbghelp_dwarf
dbghelp_macho	dbghelp_msc	dbghelp_stabs	dbghelp_symt
dc	dciman	ddeml	ddraw
ddrawex	debug_buffer	debugstr	devenum
dhcpcsvc	dialog	dib	difxapi
dinput	display	dll	dma
dmband	dmcompos	dmdump	dmfile
dmfileraw	dmime	dmloader	dmobj
dmscript	dmstyle	dmsynth	dmusic
dmusic32	dnsapi	dosmem	dpa
dplay	dpnet	dpnhpast	dpvoice
dragdrop	driver	drmclien	dsa
dsound	dsound3d	dssenh	dswave
dwmapi	dwrite	dxdiag	dxgi
dxva2	eax	edit	enhmetafile
environ	event	eventlog	exec
explorerframe	faultrep	file	fixup
fltlib	fltmgr	font	fontcache
fontsub	fps	fusion	fwpuclnt
g711	gameux	gdi	gdiplus
gecko	gl_compat	global	globalmem
glu	gpkcsp	graphics	gsm
gstreamer	handle	header	heap
hid	hlink	hlsl_parser	hnetcfg
hook	hotkey	htmlhelp	httpapi
iccvid	icm	icmp	icon
ieframe	image	imagehlp	imagelist
imm	imports	inetcomm	inetcpl
inetmib1	infosoft	initpki	inkobj
inseng	int	int21	int31
io	ipaddress	iphlpapi	itircl
itss	joycpl	joystick	jpeg
jscript	jscript_disas	jsproxy	key
keyboard	ktmw32	listbox	listview
loaddll	loadperf	local	localspl
localui	lsa	macdrv	mapi
mapistub	mci	mciavi	mcicda
mcimidi	mciqtz	mciwave	mdi
menu	message	metafile	mfplat
mgmtapi	midi	mlang	mmaux
mmc	mmdevapi	mmio	mmsys
mmtime	module	monthcal	mountmgr
mpeg3	mpr	mprapi	msacm
mscat	mscms	mscoree	msctf
msdmo	msftedit	msg	msgbox
mshtml	msi	msidb	msident
msimg32	msimtf	msisip	msisys
msls31	msnet	mspatcha	msrle32
mssign	mssip32	mstask	msvcirt
msvcm	msvcp	msvcrt	msvidc32
msvideo	mswsock	msxml	nativefont
nddeapi	ndis	netapi32	netbios
netcfgx	netprofm	newdev	nls
nonclient	normaliz	nstc	ntdll
ntdsapi	ntlm	ntoskrnl	ntprint
nvapi	nvcuda	nvcuvid	nvencodeapi
objsel	odbc	ole	oleacc
oledb	oledlg	olemalloc	olepicture
olerelay	olethk32	openal32	opencl
opengl	oss	packager	pager
palette	parsed_shader	pdh	pidgen
pidl	powermgnt	powrprof	print
printui	prntvpt	process	profile
progress	propsheet	propsys	psdrv
pstores	pulse	qcap	qcap_v4l
qedit	qmgr	qtdatahandler	qtdecoder
qtsplitter	quartz	query	ras
rasdlg	rebar	recyclebin	reg
regapi	region	relay	resource
resutils	richedit	richedit_check	richedit_lists
richedit_style	rpc	rstrtmgr	rtutils
samlib	sblaster	scarddlg	sccbase
schannel	schedsvc	scroll	scrrun
scsiport	secur32	seh	selector
sensapi	server	service	setupapi
sfc	shdocvw	shell	shlctrl
slbcsp	slc	snmpapi	snoop
sound	spoolss	static	statusbar
sti	storage	stress	string
strmbase	strmbase_qc	svrapi	sxs
sync	synchronous	syslevel	syslink
system	systray	t2embed	tab
tape	tapi	task	taskschd
text	theme_button	theme_scroll	theming
themingcombo	thread	threadpool	thunk
tid	time	timestamp	toolbar
toolhelp	tooltips	trackbar	traffic
trash	treeview	twain	typelib
uniscribe	updown	updspapi	url
urlmon	usbd	user	userenv
uxtheme	variant	vbscript	vbscript_disas
vcomp	vcomp100	vcomp90	vdmdbg
ver	virtual	volume	vssapi
vxd	wave	wavemap	wbemdisp
wbemprox	webservices	wer	wevtapi
wgl	wia	win	wincodecs
winediag	winemapi	wing	winhttp
wininet	winmm	winscard	winsock
winspool	winsta	winstation	wintab
wintab32	wintrust	wlanapi	wldap32
wmiutils	wmp	wmvcore	wnet
wpcap	wshom	wsnmp32	wtsapi
wuapi	wuaueng	x11drv	x11settings
xapofx	xaudio2	xdg	xdnd
xim	xinput	xmllite	xolehlp
xrandr	xrender	xvidmode