windbg step by step

转自：http://blog.sina.com.cn/s/blog_48ebca64010097hc.html

1. install
http://www.microsoft.com/whdc/devtools/debugging/default.mspx

download and install.

 

2. enable debug information in building process
You can modify the Makefile, just add option as below:
-MDd -Z7 -Od
Then the pdb file is created which will be used when you want to debug using windbg. Just for reference, I list the meaning of options of cl as below:

C:\>cl \help
/O2 maximize speed
/Od disable optimizations (default)
/Zi enable debugging information
/Z7 enable old-style debug info
/MD link with MSVCRT.LIB                
/MDd link with MSVCRTD.LIB debug lib

 

3. set symbol path
set symbol path to be something like:
SRV*C:\myLocalSymols*
seperated by asterisk, the first one is your local path to save the symbol files.

 

4. attach to running process
In some OS(window 2008), only administrator can attach to every process, Other users can not even if they belong to admin group.

 

4.2 open binary file
You can define arguments in the gui also.

 

5. load symbols
.reload /f
force debugger to reload symbols at once, the debugger's natural behavior is lazy mode.

 

6. set breakpoint
bp funcName - break at function funcName
bp ClassName::funcName - break at function of class
bl - list all breakpoints
bc (number) - clear breakpoint
But I do not know how to set breakpoint on specific line.

 

7. check/switch thread
~* - check all thread in current process
~1 s - switch to the first thread

 

8. show stack
kb

 

9. show variable
e{b|d|D|f|p|q|w}
But it's not so convenient since each variable type need special command, The windbg gui is preferable, please use menu("view"->"locals").

For global variable, you can use this menu("view"->"watch")

 

10. trace
p or pa or pc - step
g - continue
"Debug->Break" - stop trace

 

11. quit
You shoud detach with the process if you don't want to kill it.

 

[tips]: How to set breakpoint for daemon?

void setBreak()
{
  volatile int iii = 1;
  while(iii) {
    sleep(1);
  }
}
Here, we use keyword volatile to avoid optimize by compiler.