(gdb) frame 0
#0  0x0807b83c in ast_queue_frame (chan=0xb4f917f8, fin=0x814ee20) at channel.c:934
934             AST_LIST_INSERT_TAIL(&chan->readq, f, frame_list);
(gdb) print *chan
$1 = {tech = 0x7b74380, tech_pvt = 0xb9e2530, __begin_field = 0xb4f91800, name = 0xb59192e9 "SIP/cam-m1-0b9e2530", 
  language = 0xb5919306 "en", musicclass = 0x8141db0 "", accountcode = 0xb5919301 "mccc", call_forward = 0x8141db0 "", 
  uniqueid = 0xb59192d8 "1187371825.36640", __end_field = 0xb4f91818, __field_mgr = {pool = 0xb59192c8, size = 128, space = 67, 
    used = 61}, fds = {206, 225, -1, -1, -1, -1, 163, -1}, music_state = 0x0, generatordata = 0x0, generator = 0x0, 
  _bridge = 0xb0704e0, masq = 0x0, masqr = 0x0, cdrflags = 0, _softhangup = 0, whentohangup = 0, blocker = 41020336, lock = {
    __m_reserved = 2, __m_count = 2, __m_owner = 0x3af5, __m_kind = 1, __m_lock = {__status = 1, __spinlock = 0}}, 
  blockproc = 0x812a0ae "ast_waitfor_nandfds", appl = 0xb7ab4afc "Dial", data = 0x270d4c0 "SIP/*456@cam-m1|25", fdno = 6, 
  sched = 0xb5b74170, streamid = -1, stream = 0x0, vstreamid = 0, vstream = 0x0, oldwriteformat = 0, timingfd = 163, 
  timingfunc = 0, timingdata = 0x0, _state = AST_STATE_UP, rings = 0, cid = {cid_dnid = 0x0, cid_num = 0xa32d900 "*654", 
    cid_name = 0xa32d910 "", cid_ani = 0xba74fe8 "5025549266", cid_rdnis = 0x0, cid_pres = 0, cid_ani2 = 0, cid_ton = 0, 
    cid_tns = 0}, dtmfq = '\0' <repeats 79 times>, dtmff = {frametype = 0, subclass = 0, datalen = 0, samples = 0, mallocd = 0, 
    mallocd_hdr_len = 0, offset = 0, src = 0x0, data = 0x0, delivery = {tv_sec = 0, tv_usec = 0}, frame_list = {next = 0x0}, 
    has_timing_info = 0, ts = 0, len = 0, seqno = 0}, context = "macro-voip-out", '\0' <repeats 65 times>, 
  exten = "s\00056", '\0' <repeats 75 times>, priority = 1, macrocontext = "mccc", '\0' <repeats 75 times>, 
  macroexten = "*456", '\0' <repeats 75 times>, macropriority = 1, dialcontext = '\0' <repeats 79 times>, pbx = 0xa17d2d0, 
  amaflags = 3, cdr = 0x0, adsicpe = AST_ADSI_UNAVAILABLE, zone = 0x0, monitor = 0x0, insmpl = 0, outsmpl = 0, fin = 218, 
  fout = 0, hangupcause = 16, varshead = {first = 0xa7b5278, last = 0xa4616f8}, callgroup = 0, pickupgroup = 0, flags = 800, 
  transfercapability = 0, readq = {first = 0xb50ce2b8, last = 0x0}, alertpipe = {-1, -1}, nativeformats = 4, readformat = 4, 
  writeformat = 4, writetrans = 0x0, readtrans = 0x0, rawreadformat = 4, rawwriteformat = 4, spies = 0x0, whisper = 0x0, 
  chan_list = {next = 0xb960068}, jb = {conf = {flags = 0, max_size = -1, resync_threshold = -1, impl = '\0' <repeats 11 times>}, 
    impl = 0x0, jbobj = 0x0, timebase = {tv_sec = 0, tv_usec = 0}, next = 0, last_format = 0, logfile = 0x0, flags = 0}, 
  emulate_dtmf_digit = 0 '\0', emulate_dtmf_duration = 0, dtmf_tv = {tv_sec = 0, tv_usec = 0}, datastores = {first = 0x0, 
    last = 0x0}}
(gdb) print *f
$2 = {frametype = AST_FRAME_NULL, subclass = 0, datalen = 0, samples = 0, mallocd = 1, mallocd_hdr_len = 128, offset = 64, 
  src = 0x0, data = 0x0, delivery = {tv_sec = 0, tv_usec = 0}, frame_list = {next = 0x0}, has_timing_info = 0, ts = 0, len = 0, 
  seqno = 0}
(gdb)