You're not skipping gdb's ptrace, you're skipping when iTunes calls it. iTunes calls ptrace() with PT_DENY_ATTACH to disallow gdb from attaching to it, which th

You're not skipping gdb's ptrace, you're skipping when iTunes calls it. iTunes calls ptrace() with PT_DENY_ATTACH to disallow gdb from attaching to it, which this method easily skips to let you attach to iTunes without any issues.