Using the GNU Debugger GDB

The following is a sample session using gdb:

gdb /path/to/program
GNU gdb 6.3.50-20050815 (Apple version gdb-962) (Sat Jul 26 08:14:40 UTC 2008)
Copyright 2004 Free Software Foundation, Inc.

(gdb) break malloc_error_break
Breakpoint 1 at 0x1374bc6a7e31a11

(gdb) break SomeClass::~SomeClass()
Breakpoint 2 at 0x1001a22e6: file ../../../../src/code/SomeClass.h, line 13.
Breakpoint 3 at 0x1001a2248: file ../../../../src/code/SomeClass.h, line 13.
warning: Multiple breakpoints were set.
Use the "delete" command to delete unwanted breakpoints.

(gdb) delete 3

(gdb) break myLicenseManager.cxx:330
Breakpoint 3 at 0xa2a9d: file ../../src/code/myLicenseManager.cxx, line 330.

(gdb) run
Breakpoint 1, myGraphInventor::UpdateColor (this=0x6692e00, aColor=@0x2e6c3cb0) at ../../src/myGraphInventor.cxx:639
639       std::cerr << "myGraphInventor::UpdateColor()" << std::endl;

(gdb) list
634                                                              myColor*& aColor)
638     {
639       std::cerr << "myGraphInventor::UpdateColor()" << std::endl;
640
641       // switch off color coding
642       switch (mCurrentColor) {

(gdb) run
Program received signal EXC_BAD_ACCESS, Could not access memory.
Reason: KERN_INVALID_ADDRESS at address: 0x0000000000000001
0x00007fff8320c89c in std::string::find_last_of ()

(gdb) backtrace
#0  0x00007fff8320c89c in std::string::find_last_of ()
#1  0x000000010059e3d9 in myFileTools::GetPath (aFileName=@0x1) at ../../src/myFileTools.cpp:44
#2  0x0000000103b8e646 in QAction::triggered ()
#3  0x0000000103b90814 in QAction::activate ()
#4  0x0000000103f09e6f in QAbstractButtonPrivate::click ()

(gdb) info threads
  4 process 9011 thread 0x6647  0x00007fff83288642 in kevent ()
* 3 process 9011 thread 0x363f  0x00007fffffe0026d in ?? ()
  2 process 9011 thread 0x3a07  0x00007fff83261d02 in __semwait_signal ()
  1 process 9011 local thread 0x2d03  0x00007fff8320c89c in std::string::find_last_of ()

(gdb) thread 1
[Switching to thread 1 (process 9011 local thread 0x2d03)]
0x00007fff8320c89c in std::string::find_last_of ()

# using the Tab key (denoted [TAB] here) to auto-complete code lines:
(gdb) break myTexture[TAB]
Display all 964 possibilities? (y or n) n

(gdb) break myTextureFragmentProgram[TAB]
myTextureFragmentProgram.cxx
myTextureFragmentProgram.h
myTextureFragmentProgram::Bias(float, float)
myTextureFragmentProgram::Colorize(Color const&)
myTextureFragmentProgram::Disable() const
myTextureFragmentProgram::Enable() const
myTextureFragmentProgram::Interpolate() const
myTextureFragmentProgram::Interpolate(bool)
myTextureFragmentProgram::SetSource() const
myTextureFragmentProgram::SetNumber(int)

# use single quotation marks to enclose spaces:
(gdb) break 'bpTextureFragmentProgram::Enable() const'
Breakpoint 4 at 0x1003f5604: file ../../src/myTextureFragmentProgram.cxx, line 50.



(gdb) quit
The program is running.  Exit anyway? (y or n) y

A nice collection of commonly used GDB commands can be found here: http://www.yolinux.com/TUTORIALS/GDB-Commands.html