winedbg - Wine debugger
winedbg [ options ] [ program_name [ program_arguments ] | wpid ]
winedbg --gdb [ options ] [ program_name [ program_arguments ] | wpid ]
winedbg --auto wpid
winedbg --minidump [ file.mdmp ] wpid
winedbg is a debugger for Wine. It allows:
- + debugging native Win32 applications
- + debugging Winelib applications
- + being a drop-in replacement for Dr Watson
winedbg can be used in five modes. The first argument to the program determines the mode winedbg will run in.
- Without any explicit mode, this is standard winedbg operating mode. winedbg will act as the front end for the user.
- winedbg will be used as a proxy for gdb. gdb will be the front end for command handling, and winedbg will proxy all debugging requests from gdb to the Win32 APIs.
- This mode is used when winedbg is set up in AeDebug registry entry as the default debugger. winedbg will then display basic information about a crash. This is useful for users who don't want to debug a crash, but rather gather relevant information about the crash to be sent to developers.
- This mode is similar to the --auto one, except that instead of printing the information on the screen (as --auto does), it's saved into a minidump file. The name of the file is either passed on the command line, or generated by WineDbg when none is given. This file could later on be reloaded into winedbg for further examination.
- In this mode winedbg reloads the state of a debuggee which has been saved into a minidump file. See either the minidump command below, or the --minidump mode.
When in default mode, the following options are available:
- winedbg will execute the command string as if it was keyed on winedbg command line, and then will exit. This can be handy for getting the pid of running processes (winedbg --command "info proc").
- winedbg will execute the list of commands contained in file filename as if they were keyed on winedbg command line, and then will exit.
When in gdb proxy mode, the following options are available:
- gdb will not be automatically started. Relevant information for starting gdb is printed on screen. This is somehow useful when not directly using gdb but some graphical front-ends, like ddd or kgbd.
- Start the gdb server on the given port. If this option is not specified, a randomly chosen port will be used. If --no-start is specified, the port used will be printed on startup.
- This will run gdb in its own xterm instead of using the current Unix console for textual display.
In all modes, the rest of the command line, when passed, is used to identify which programs, if any, has to debugged:
- This is the name of an executable to start for a debugging session. winedbg will actually create a process with this executable. If programs_arguments are also given, they will be used as arguments for creating the process to be debugged.
- winedbg will attach to the process which Windows pid is wpid. Use the info proc command within winedbg to list running processes and their Windows pids.
- If nothing is specified, you will enter the debugger without any run nor attached process. You'll have to do the job yourself.
Default mode, and while reloading a minidump file:
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.
- Aborts the debugger.
- Exits the debugger.
- Attach to a Wine process (N is its Windows ID, numeric or hexadecimal). IDs can be obtained using the info process command. Note the info process command returns hexadecimal values
- Detach from a Wine-process.
- Change the current thread to N (its Windows TID, numeric or hexadecimal).
- Re-run the same process with the same arguments. Note: all breakpoints of precedent process are no longer available.
run arg1 arg2...
- Re-run the same process with arguments arg1 arg2.... Note: all breakpoints of precedent process are no longer available.
- Prints some help on the commands.
- Prints some help on info commands
Flow control commands
- Continue execution until next breakpoint or exception.
- Pass the exception event up to the filter chain.
- Continue execution until next C line of code (enters function call)
- Continue execution until next C line of code (doesn't enter function call)
- Execute next assembly instruction (enters function call)
- Execute next assembly instruction (doesn't enter function call)
- Execute 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.
- Enables (break|watch)-point N
- Disables (break|watch)-point N
- Deletes (break|watch)-point 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
- Adds a breakpoint at the address of symbol id
break id N
- Adds a breakpoint at the line N inside symbol id.
- Adds a breakpoint at line N of current source file.
- Adds a breakpoint at current $PC address.
watch * N
- Adds a watch command (on write) at address N (on 4 bytes).
- Adds a watch command (on write) at the address of symbol id. Size depends on size of id.
rwatch * N
- Adds a watch command (on read) at address N (on 4 bytes).
- Adds a watch command (on read) at the address of symbol id. Size depends on size of id.
- 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).
- Print calling stack of current thread.
- 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).
- Goes up one frame in current thread's stack
- Goes up N frames in current thread's stack
- Goes down one frame in current thread's stack
- Goes down N frames in current thread's stack
- Sets N as the current frame for current thread's stack.
- Prints information on local variables for current function frame.
Directory & source file manipulation
- Prints the list of dirs where source files are looked for.
- Adds pathname to the list of dirs where to look for source files
- Deletes the list of dirs where to look for source files
- Loads external symbol definition file pathname
symbolfile pathname N
- Loads external symbol definition file pathname (applying an offset of N to addresses)
- Lists 10 source lines forwards from current position.
- Lists 10 source lines backwards from current position
- Lists 10 source lines from line N in current file
- Lists 10 source lines from line N in file pathname
- 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
- lists source lines from line 1 up to 56 in file foo.c
A display is an expression that's evaluated and printed after the execution of any winedbg command.
- Lists the active displays
- 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
- Deletes display N
- Disassemble from current position
- Disassemble from address expr
- Disassembles code between addresses specified by the two expressions
Memory (reading, writing, typing)
- Examines memory at address expr
x /fmt expr
- Examines memory at address expr using format fmt
- 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
- Prints the C type of expression expr
fmt is either letter or count letter, where letter can be:
|s||an ASCII string|
|u||a UTF16 Unicode string|
|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|
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 ID from, e.g. USER32!CreateWindowExA.
- In a cast operation, when specifying a structure or a union, you must use the struct or union keyword (even if your program uses a typedef).
When specifying an identifier, 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.
minidump file.mdmp saves the debugging context of the debuggee into a minidump file called file.mdmp.
Information on Wine internals
- Lists all Windows classes registered in Wine
info class id
- Prints information on Windows class id
- 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
- Prints the value of the CPU registers
- Prints the value of the CPU and Floating Point registers
- Lists all allocated segments (i386 only)
info segment N
- Prints information on segment N (i386 only)
- Prints the values on top of the stack
- Lists all virtual mappings used by the debugged program
info map N
- Lists all virtual mappings used by the program of Windows pid N
- Displays the window hierarchy starting from the desktop window
info wnd N
- Prints information of Window of handle N
- Lists all w-processes in Wine session
- Lists all w-threads in Wine session
- Lists the exception frames (starting from current stack frame). You can also pass, as optional argument, a thread id (instead of current thread) to examine its exception frames.
Debug messages can be turned on and off as you are debugging using the set command, but only for channels initialized with the WINEDEBUG environment variable.
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 - all
- Turns off fixme class on all channels
See the gdb documentation for all the gdb commands.
However, a few Wine extensions are available, through the monitor command:
- Lists all windows in the Wine session
- Lists all processes in the Wine session
- Displays memory mapping of debugged process
Auto and minidump modes:
Since no user input is possible, no commands are available.
- When used in gdb proxy mode, WINE_GDB specifies the name (and the path) of the executable to be used for gdb. "gdb" is used by default.
The first version was written by Eric Youngdale.
See Wine developers list for the rest of contributors.
Bugs can be reported on the Wine bug tracker
winedbg is part of the Wine distribution, which is available through WineHQ, the Wine development headquarters