dave@akai ~ % lldb process attach -n beam.smp Warning: program arguments are ignored when attaching. Attaching to process with: process attach -n "beam.smp" Process 94307 stopped Executable module set to "/usr/local/Cellar/erlang/R15B01/lib/erlang/erts-5.9.1/bin/beam.smp". Architecture set to: x86_64. (lldb) c Process 94307 resuming Process 94307 stopped * thread #6: tid = 0x2503, 0x00007fff89f8c1ec libsystem_c.dylib`flockfile + 15, stop reason = EXC_BAD_ACCESS (code=1, address=0x68) frame #0: 0x00007fff89f8c1ec libsystem_c.dylib`flockfile + 15 libsystem_c.dylib`flockfile + 15: -> 0x7fff89f8c1ec: movq 104(%rbx), %rdi 0x7fff89f8c1f0: cmpq %rax, 72(%rdi) 0x7fff89f8c1f4: jne 0x00007fff89f8c1fe ; flockfile + 33 0x7fff89f8c1f6: incl 80(%rdi) (lldb) thread list Process 94307 stopped thread #1: tid = 0x1f03, 0x00007fff921ebdf2 libsystem_kernel.dylib`select$DARWIN_EXTSN + 10 thread #2: tid = 0x2103, 0x00007fff921ecaf2 libsystem_kernel.dylib`read + 10 thread #3: tid = 0x2203, 0x00007fff921ebbca libsystem_kernel.dylib`__psynch_cvwait + 10 thread #4: tid = 0x2303, 0x00007fff921ebbca libsystem_kernel.dylib`__psynch_cvwait + 10 thread #5: tid = 0x2403, 0x00000000167bacf3 beam.smp`sched_spin_wait + 37 * thread #6: tid = 0x2503, 0x00007fff89f8c1ec libsystem_c.dylib`flockfile + 15, stop reason = EXC_BAD_ACCESS (code=1, address=0x68) thread #7: tid = 0x2603, 0x00007fff921ebdf2 libsystem_kernel.dylib`select$DARWIN_EXTSN + 10 thread #8: tid = 0x2703, 0x00007fff921ebbca libsystem_kernel.dylib`__psynch_cvwait + 10 thread #9: tid = 0x2803, 0x00007fff921ebbca libsystem_kernel.dylib`__psynch_cvwait + 10 thread #10: tid = 0x2903, 0x00007fff921ebbca libsystem_kernel.dylib`__psynch_cvwait + 10 thread #11: tid = 0x2a03, 0x00007fff921ebbca libsystem_kernel.dylib`__psynch_cvwait + 10 thread #12: tid = 0x2b03, 0x00007fff921ebbca libsystem_kernel.dylib`__psynch_cvwait + 10 thread #13: tid = 0x2c03, 0x00007fff921ebbca libsystem_kernel.dylib`__psynch_cvwait + 10 (lldb) thread backtrace all thread #1: tid = 0x1f03, 0x00007fff921ebdf2 libsystem_kernel.dylib`select$DARWIN_EXTSN + 10 frame #0: 0x00007fff921ebdf2 libsystem_kernel.dylib`select$DARWIN_EXTSN + 10 frame #1: 0x0000000016841537 beam.smp`erts_sys_main_thread + 205 frame #2: 0x000000001677036f beam.smp`erl_start + 4044 frame #3: 0x000000001675a3d5 beam.smp`main + 9 frame #4: 0x000000001675a3c4 beam.smp`start + 52 thread #2: tid = 0x2103, 0x00007fff921ecaf2 libsystem_kernel.dylib`read + 10 frame #0: 0x00007fff921ecaf2 libsystem_kernel.dylib`read + 10 frame #1: 0x0000000016841a33 beam.smp`signal_dispatcher_thread_func + 45 frame #2: 0x0000000016890203 beam.smp`thr_wrapper + 111 frame #3: 0x00007fff89f448bf libsystem_c.dylib`_pthread_start + 335 frame #4: 0x00007fff89f47b75 libsystem_c.dylib`thread_start + 13 thread #3: tid = 0x2203, 0x00007fff921ebbca libsystem_kernel.dylib`__psynch_cvwait + 10 frame #0: 0x00007fff921ebbca libsystem_kernel.dylib`__psynch_cvwait + 10 frame #1: 0x00007fff89f48274 libsystem_c.dylib`_pthread_cond_wait + 840 frame #2: 0x000000001688e5bd beam.smp`ethr_cond_wait + 9 frame #3: 0x000000001678e3af beam.smp`sys_msg_dispatcher_func + 327 frame #4: 0x0000000016890203 beam.smp`thr_wrapper + 111 frame #5: 0x00007fff89f448bf libsystem_c.dylib`_pthread_start + 335 frame #6: 0x00007fff89f47b75 libsystem_c.dylib`thread_start + 13 thread #4: tid = 0x2303, 0x00007fff921ebbca libsystem_kernel.dylib`__psynch_cvwait + 10 frame #0: 0x00007fff921ebbca libsystem_kernel.dylib`__psynch_cvwait + 10 frame #1: 0x00007fff89f48274 libsystem_c.dylib`_pthread_cond_wait + 840 frame #2: 0x000000001688e5bd beam.smp`ethr_cond_wait + 9 frame #3: 0x0000000016842234 beam.smp`child_waiter + 650 frame #4: 0x0000000016890203 beam.smp`thr_wrapper + 111 frame #5: 0x00007fff89f448bf libsystem_c.dylib`_pthread_start + 335 frame #6: 0x00007fff89f47b75 libsystem_c.dylib`thread_start + 13 thread #5: tid = 0x2403, 0x00000000167bacf3 beam.smp`sched_spin_wait + 37 frame #0: 0x00000000167bacf3 beam.smp`sched_spin_wait + 37 frame #1: 0x00000000167b3e21 beam.smp`schedule + 6745 frame #2: 0x00000000168203e6 beam.smp`process_main + 1265 frame #3: 0x00000000167afbfc beam.smp`sched_thread_func + 506 frame #4: 0x0000000016890203 beam.smp`thr_wrapper + 111 frame #5: 0x00007fff89f448bf libsystem_c.dylib`_pthread_start + 335 frame #6: 0x00007fff89f47b75 libsystem_c.dylib`thread_start + 13 * thread #6: tid = 0x2503, 0x00007fff89f8c1ec libsystem_c.dylib`flockfile + 15, stop reason = EXC_BAD_ACCESS (code=1, address=0x68) frame #0: 0x00007fff89f8c1ec libsystem_c.dylib`flockfile + 15 frame #1: 0x00007fff89f2c938 libsystem_c.dylib`putc + 32 frame #2: 0x000000001687645c beam.smp`write_buf + 273 frame #3: 0x0000000016876a91 beam.smp`insert_buf + 481 frame #4: 0x000000001687608a beam.smp`put_chars + 9 frame #5: 0x00000000168756ba beam.smp`ttysl_from_erlang + 110 frame #6: 0x00000000167a1350 beam.smp`erts_write_to_port + 3056 frame #7: 0x00000000167a273e beam.smp`erts_port_command + 256 frame #8: 0x0000000016799db7 beam.smp`do_send + 1319 frame #9: 0x00000000167995cf beam.smp`erl_send + 38 frame #10: 0x00000000168248ec beam.smp`process_main + 18935 frame #11: 0x00000000167afbfc beam.smp`sched_thread_func + 506 frame #12: 0x0000000016890203 beam.smp`thr_wrapper + 111 frame #13: 0x00007fff89f448bf libsystem_c.dylib`_pthread_start + 335 frame #14: 0x00007fff89f47b75 libsystem_c.dylib`thread_start + 13 thread #7: tid = 0x2603, 0x00007fff921ebdf2 libsystem_kernel.dylib`select$DARWIN_EXTSN + 10 frame #0: 0x00007fff921ebdf2 libsystem_kernel.dylib`select$DARWIN_EXTSN + 10 frame #1: 0x0000000016848988 beam.smp`erts_poll_wait_nkp + 355 frame #2: 0x000000001684a762 beam.smp`erts_check_io_nkp + 151 frame #3: 0x00000000167b4304 beam.smp`schedule + 7996 frame #4: 0x00000000168203e6 beam.smp`process_main + 1265 frame #5: 0x00000000167afbfc beam.smp`sched_thread_func + 506 frame #6: 0x0000000016890203 beam.smp`thr_wrapper + 111 frame #7: 0x00007fff89f448bf libsystem_c.dylib`_pthread_start + 335 frame #8: 0x00007fff89f47b75 libsystem_c.dylib`thread_start + 13 thread #8: tid = 0x2703, 0x00007fff921ebbca libsystem_kernel.dylib`__psynch_cvwait + 10 frame #0: 0x00007fff921ebbca libsystem_kernel.dylib`__psynch_cvwait + 10 frame #1: 0x00007fff89f48274 libsystem_c.dylib`_pthread_cond_wait + 840 frame #2: 0x00000000168904ce beam.smp`wait__ + 195 frame #3: 0x00000000167b3e4d beam.smp`schedule + 6789 frame #4: 0x00000000168203e6 beam.smp`process_main + 1265 frame #5: 0x00000000167afbfc beam.smp`sched_thread_func + 506 frame #6: 0x0000000016890203 beam.smp`thr_wrapper + 111 frame #7: 0x00007fff89f448bf libsystem_c.dylib`_pthread_start + 335 frame #8: 0x00007fff89f47b75 libsystem_c.dylib`thread_start + 13 thread #9: tid = 0x2803, 0x00007fff921ebbca libsystem_kernel.dylib`__psynch_cvwait + 10 frame #0: 0x00007fff921ebbca libsystem_kernel.dylib`__psynch_cvwait + 10 frame #1: 0x00007fff89f48274 libsystem_c.dylib`_pthread_cond_wait + 840 frame #2: 0x00000000168904ce beam.smp`wait__ + 195 frame #3: 0x00000000167b3e4d beam.smp`schedule + 6789 frame #4: 0x00000000168203e6 beam.smp`process_main + 1265 frame #5: 0x00000000167afbfc beam.smp`sched_thread_func + 506 frame #6: 0x0000000016890203 beam.smp`thr_wrapper + 111 frame #7: 0x00007fff89f448bf libsystem_c.dylib`_pthread_start + 335 frame #8: 0x00007fff89f47b75 libsystem_c.dylib`thread_start + 13 thread #10: tid = 0x2903, 0x00007fff921ebbca libsystem_kernel.dylib`__psynch_cvwait + 10 frame #0: 0x00007fff921ebbca libsystem_kernel.dylib`__psynch_cvwait + 10 frame #1: 0x00007fff89f48274 libsystem_c.dylib`_pthread_cond_wait + 840 frame #2: 0x00000000168904ce beam.smp`wait__ + 195 frame #3: 0x00000000167b3e4d beam.smp`schedule + 6789 frame #4: 0x00000000168203e6 beam.smp`process_main + 1265 frame #5: 0x00000000167afbfc beam.smp`sched_thread_func + 506 frame #6: 0x0000000016890203 beam.smp`thr_wrapper + 111 frame #7: 0x00007fff89f448bf libsystem_c.dylib`_pthread_start + 335 frame #8: 0x00007fff89f47b75 libsystem_c.dylib`thread_start + 13 thread #11: tid = 0x2a03, 0x00007fff921ebbca libsystem_kernel.dylib`__psynch_cvwait + 10 frame #0: 0x00007fff921ebbca libsystem_kernel.dylib`__psynch_cvwait + 10 frame #1: 0x00007fff89f48274 libsystem_c.dylib`_pthread_cond_wait + 840 frame #2: 0x00000000168904ce beam.smp`wait__ + 195 frame #3: 0x00000000167b3e4d beam.smp`schedule + 6789 frame #4: 0x00000000168203e6 beam.smp`process_main + 1265 frame #5: 0x00000000167afbfc beam.smp`sched_thread_func + 506 frame #6: 0x0000000016890203 beam.smp`thr_wrapper + 111 frame #7: 0x00007fff89f448bf libsystem_c.dylib`_pthread_start + 335 frame #8: 0x00007fff89f47b75 libsystem_c.dylib`thread_start + 13 thread #12: tid = 0x2b03, 0x00007fff921ebbca libsystem_kernel.dylib`__psynch_cvwait + 10 frame #0: 0x00007fff921ebbca libsystem_kernel.dylib`__psynch_cvwait + 10 frame #1: 0x00007fff89f48274 libsystem_c.dylib`_pthread_cond_wait + 840 frame #2: 0x00000000168904ce beam.smp`wait__ + 195 frame #3: 0x00000000167b3e4d beam.smp`schedule + 6789 frame #4: 0x00000000168203e6 beam.smp`process_main + 1265 frame #5: 0x00000000167afbfc beam.smp`sched_thread_func + 506 frame #6: 0x0000000016890203 beam.smp`thr_wrapper + 111 frame #7: 0x00007fff89f448bf libsystem_c.dylib`_pthread_start + 335 frame #8: 0x00007fff89f47b75 libsystem_c.dylib`thread_start + 13 thread #13: tid = 0x2c03, 0x00007fff921ebbca libsystem_kernel.dylib`__psynch_cvwait + 10 frame #0: 0x00007fff921ebbca libsystem_kernel.dylib`__psynch_cvwait + 10 frame #1: 0x00007fff89f48274 libsystem_c.dylib`_pthread_cond_wait + 840 frame #2: 0x00000000168904ce beam.smp`wait__ + 195 frame #3: 0x00000000167afdab beam.smp`aux_thread + 343 frame #4: 0x0000000016890203 beam.smp`thr_wrapper + 111 frame #5: 0x00007fff89f448bf libsystem_c.dylib`_pthread_start + 335 frame #6: 0x00007fff89f47b75 libsystem_c.dylib`thread_start + 13 (lldb) frame variable (lldb)