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    <p>To answer your first question, of course it contains your program's instructions: you can only execute what you can access. To get at the address of your instructions, you can take the address of a function and start printing from there. You can then use a library like <a href="http://udis86.sourceforge.net/" rel="nofollow">udis86</a> to disassemble them. Note however, that your compiler isn't required to order the functions in any specific way, so starting at <code>main</code> and reading from there isn't guaranteed to get everything, might trample on un-allocated memory.</p> <p>To get at the entire instruction memory range (you're looking for the <code>.text</code> segment), you can look up the address+size from your operating system (In Linux, that info will be in <code>/proc/[pid]/maps</code>, in OS X you can either use <code>vmmap</code> or ask the kernel via the <code>mach_vm_region()</code> kernel trap), and then just read the memory directly. You can also use <code>nm</code> to dump the symbols of your program, isolate all that point to the <code>.text</code> segment (They should be marked with <code>T</code> in <code>nm</code> output) and dump those. This is not a good method, since you'd have to disassemble everything to determine where they end in the case there's padding between them.</p> <p>All the mapped memory is accessible, but not all of it will be writeable (The <code>.text</code> segment wouldn't be). One thing to keep in mind, the addresses will probably not be stable invocation to invocation if your operating system implements ASLR.</p> <p>To address your second question, yes you can print your own stack and symbolicate it with the help of third-party libraries, but not the way you're trying to do it. Stack typically grows <em>down</em> (i.e. Starts at a high address and moves towards lower addresses. As an exercise to the reader, disassemble one of your functions via <code>gdb</code> or another disassembler and look how memory on the stack gets allocated during your function prolog), so your for-loop will never run as <code>BASE</code> will probably always be larger than the address of <code>sentinel</code>.</p>
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    1. COThanks for all the tips! I'll look at `/proc/[pid]/maps`, very interesting. I didn't want to `nm`, I just wanted to poke around the live memory during execution. Of course the stack goes down, d'oh. I'll fix that!
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