NAME

pdb - The Parrot debugger

SYNOPSIS

 pdb programfile

disassemble: Disassemble the bytecode.; Use this if you have a PBC file but not the PASM.
load: Load a source code file.
list or l: List the source code file.
run or r: Run the program.
break or b: Add a breakpoint.
watch or w: Add a watchpoint.
delete or d: Delete a breakpoint.
disable: Disable a breakpoint.
enable: Reenable a disabled breakpoint.
continue or c: Continue the program execution.
next or n: Run the next instruction
eval or e: Run an instruction.
trace or t: Trace the next instruction.
print or p: Print the interpreter registers.
stack or s: Examine the stack.
info: Print interpreter information.
quit or q: Exit the debugger.
help or h: Print the help.

You can also debug Parrot code by using the debug_init, debug_load and debug_break ops in ops/debug.ops.

int main(int argc, char *argv[]): Reads the PASM or PBC file from argv[1], loads it, and then calls Parrot_debug().
static void PDB_printwelcome(void): Prints out the welcome string.

The debugger now uses it's own interpreter. User code is run in Interp* debugee. We have:

  debug_interp->pdb->debugee->debugger
    ^                            |
    |                            v
    +------------- := -----------+

Debug commands are mostly run inside the debugger. User code runs of course in the debugee.

Check the user input for bad commands, it's quite easy to make it bang now, try listing the source before loading or disassembling it.