anyone knows a debugger which let me trace every function call made?
is gdb able to do this?

i tried ltrace, but i only get "Error: call nesting too deep!"
and strace only traces system calls, but i want function calls too

thx@ll

gdb can, pretty much. The 'bt' command will show a complete backtrace of the program, up until the segfault (or other signal). It won't, however, actually show you incidental function calls (if I call a function Function1(), and then call another one - Function2(), and a sigfault happens in Function2(), you won't see any record of Function1() anywhere in the backtrace).

bt only works with signals, not?

but i would need a complete program flow

not only on error

cause i have a bug in my app and it begins to be very very complex and it takes very long to identify such problems

any hints on debugging an app with many childs (10 to 100 childs)?

Oh, UGH. Yeah, gdb with threaded programs is going to be nine kinds of hell, no matter which way you slice it.
If it's a logic bug somewhere, the only thing I can suggest is cut it down to 1 child process at a time, and start working with breakpoints, printing out all of the frame information at each breakpoint.
If it's something more complex, like a race condition...I'm not sure what to tell you. Those are usually manual and painful to debug, and if using a tool a more sophisticated one than plain gdb is probably necessary. A quick google search revealed a tool called 'smartGDB', which appears to have support for debugging individual threads. It looks like it's not been updated since 1999, but it was at version 1.0 then. That (or something like it) may be worth a shot :-/