Most of commands used in winedbg are similar to the ones from gdb. Please refer to the gdb documentations for some more details. See the gdb differences section later on to get a list of variations from gdb commands.

Misc. commands

abort

Aborts the debugger.

quit

Exits the debugger.

attach N

Attach to a Wine-process (N is its ID, numeric or hexadecimal). IDs can be obtained using the info process command. Note the info process command returns hexadecimal values

detach

Detach from a Wine-process.

Help commands

help

Prints some help on the commands.

help info

Prints some help on info commands

Flow control commands

cont

Continue execution until next breakpoint or exception.

pass

Pass the exception event up to the filter chain.

step

Continue execution until next C line of code (enters function call)

next

Continue execution until next C line of code (doesn't enter function call)

stepi

Execute next assembly instruction (enters function call)

nexti

Execute next assembly instruction (doesn't enter function call)

finish

Excute until return of current function is reached.

cont, step, next, stepi, nexti can be postfixed by a number (N), meaning that the command must be executed N times before control is returned to the user.

Breakpoints, watchpoints

enable N

Enables (break|watch)-point #N

disable

Disables (break|watch)-point #N

delete

Deletes (break|watch)-point #N

cond N

Removes any existing condition to (break|watch)-point N

cond N <expr>

Adds condition <expr> to (break|watch)-point #N. <expr> will be evaluated each time the (break|watch)-point is hit. If the result is a zero value, the breakpoint isn't triggered.

break * N

Adds a breakpoint at address N

break <id>

Adds a breakpoint at the address of symbol <id>

break <id> N

Adds a breakpoint at the line N inside symbol <id>.

break N

Adds a breakpoint at line N of current source file.

break

Adds a breakpoint at current PC address.

watch * N

Adds a watch command (on write) at address N (on 4 bytes).

watch <id>

Adds a watch command (on write) at the address of symbol <id>. Size depends on size of <id>.

info break

Lists all (break|watch)-points (with their state).

You can use the symbol EntryPoint to stand for the entry point of the Dll.

When setting a (break|watch)-point by <id>, if the symbol cannot be found (for example, the symbol is contained in a not yet loaded module), winedbg will recall the name of the symbol and will try to set the breakpoint each time a new module is loaded (until it succeeds).

Stack manipulation

bt

Print calling stack of current thread.

bt N

Print calling stack of thread of ID N. Note: this doesn't change the position of the current frame as manipulated by the up & dn commands).

up

Goes up one frame in current thread's stack

up N

Goes up N frames in current thread's stack

dn

Goes down one frame in current thread's stack

dn N

Goes down N frames in current thread's stack

frame N

Sets N as the current frame for current thread's stack.

info locals

Prints information on local variables for current function frame.

Directory & source file manipulation

show dir

Prints the list of dir:s where source files are looked for.

dir <pathname>

Adds <pathname> to the list of dir:s where to look for source files

dir

Deletes the list of dir:s where to look for source files

symbolfile <pathname>

Loads external symbol definition symbolfile <pathname>

symbolfile <pathname> N

Loads external symbol definition symbolfile <pathname> (applying an offset of N to addresses)

list

Lists 10 source lines forwards from current position.

list -

Lists 10 source lines backwards from current position

list N

Lists 10 source lines from line #N in current file

list <pathname>:N

Lists 10 source lines from line #N in file <pathname>

list <id>

Lists 10 source lines of function <id>

list * N

Lists 10 source lines from address N

You can specify the end target (to change the 10 lines value) using the ',' separator. For example:

list 123, 234

lists source lines from line 123 up to line 234 in current file
list foo.c:1,56

lists source lines from line 1 up to 56 in file foo.c 

Displaying

A display is an expression that's evaluated and printed after the
execution of any winedbg's command.
display

info display

Lists the active displays
display <expr>

Adds a display for expression expr>
display /fmt <expr>

Adds a display for expression <expr>. Printing evaluated
<expr> is done using the given format (see print command
for more on formats)
del display N

undisplay N

Deletes display #N

Disassembly
disas

Disassemble from current position
disas <expr>

Disassemble from address <expr>
disas <expr>,<expr>

Disassembles code between addresses specified by the two <expr>:s

Memory (reading, writing, typing)
x <expr>

Examines memory at <expr> address
x /fmt <expr>

Examines memory at <expr> address using format /fmt
print <expr>

Prints the value of <expr> (possibly using its type)
print /fmt <expr>

Prints the value of <expr> (possibly using its type)
set <var> = <expr>

Writes the value of <expr> in <var> variable.
whatis <expr>

Prints the C type of expression <expr>

/fmt

is either /<letter> or /<count><letter>. <letter>
can be:
s

an ASCII string
u

an Unicode UTF16 string
i

instructions (disassemble)
x

32 bit unsigned hexadecimal integer
d

32 bit signed decimal integer
w

16 bit unsigned hexadecimal integer
c

character (only printable 0x20-0x7f are actually printed)
b

8 bit unsigned hexadecimal integer
g

Win32 GUID

Expressions

Expressions in Wine Debugger are mostly written in a C form. However,
there are a few discrepancies:

Identifiers can take a '!' in their names. This allows mainly to
specify a module where to look the module from: USER32!CreateWindowExA.

In cast operation, when specifying a structure or an union, you must
use the struct or union key word (even if your program uses a typedef). 

When specifying an identifier <id>, if several symbols with
this name exist, the debugger will prompt for the symbol you want to
use. Pick up the one you want from its number.

Misc.

minidump file.mdmp

saves the debugging context of the debuggee into a minidump file called 
file.mdmp

Information on Wine's internals
info class

Lists all Windows' class registered in Wine
info class <id>

Prints information on Windows's class <id>
info share

Lists all the dynamic libraries loaded in the debugged program
(including .so files, NE and PE DLLs)
info share N

Prints information on module at address N
info regs

Prints the value of the CPU registers
info segment

Lists all allocated segments (i386 only)
info segment N

Prints information on segment N (i386 only)
info stack

Prints the values on top of the stack
info map

Lists all virtual mappings used by the debugged program
info map N

Lists all virtual mappings used by the program of pid N
info wnd

Displays the window hierarchy starting from the desktop window
info wnd N

Prints information of Window of handle N
info process

Lists all w-processes in Wine session
info thread

Lists all w-threads in Wine session
info exception

Lists the exception frames (starting from current stack frame)

It is possible to turn on and off Wine's debug messages as you are
debugging using the set command. 
set + warn win

Turns on warn on 'win' channel
set + win

Turns on warn/fixme/err/trace on 'win' channel
set - win

Turns off warn/fixme/err/trace on 'win' channel
set - fixme

Turns off the 'fixme' class on all channels

See the gdb documentation for all the gdb commands.

However, a few Wine's extension are available, through the monitor command:

monitor wnd

Lists all window in the Wine session

monitor proc

Lists all processes in the Wine session

monitor mem

Displays memory mapping of debugged process

Since no user input is possible, no commands are available.