#0  0x00c66909 in free () from /lib/tls/libc.so.6
(gdb) bt
#0  0x00c66909 in free () from /lib/tls/libc.so.6
#1  0x00c6328b in _IO_free_backup_area_internal () from /lib/tls/libc.so.6
#2  0x00c635b4 in __underflow () from /lib/tls/libc.so.6
#3  0x00c62b23 in _IO_file_xsgetn_internal () from /lib/tls/libc.so.6
#4  0x00c639e8 in _IO_sgetn_internal () from /lib/tls/libc.so.6
#5  0x00c57c19 in fread () from /lib/tls/libc.so.6
#6  0x009556cb in wav_read (s=0x8701538, whennext=0xd30804) at format_wav.c:378
#7  0x0809ddf3 in ast_readaudio_callback (s=0x8701538) at file.c:740
#8  0x0809df1e in ast_fsread_audio (data=0xd30804) at file.c:791
#9  0x080f510a in ast_sched_runq (con=0x892eaf0) at sched.c:363
#10 0x0809f192 in waitstream_core (c=0x87f36e8, breakon=Variable "breakon" is not available.
) at file.c:1289
#11 0x0809f74c in ast_waitstream (c=0xd30804, breakon=0x0) at file.c:1305
#12 0x005c5738 in agent_call (ast=0x87bd4d0, dest=0xb761a496 "3671", timeout=0) at chan_agent.c:764
#13 0x0808030e in ast_call (chan=0x87bd4d0, addr=0xd30804 "", timeout=13830148) at channel.c:3407
#14 0x0052426b in ring_entry (qe=0xb761c840, tmp=0x8a60c88, busies=0xb761a7a4) at app_queue.c:1985
#15 0x00524a9c in ring_one (qe=0xb761c840, outgoing=0x8a60c88, busies=0xb761a7a4) at app_queue.c:2063
#16 0x00525d45 in try_calling (qe=0xb761c840, options=Variable "options" is not available.
) at app_queue.c:2954
#17 0x0052b265 in queue_exec (chan=0x892b988, data=0xb761cc70) at app_queue.c:4077
#18 0x080c30ef in pbx_exec (c=0x892b988, app=0x86a3370, data=0xb761cc70) at /usr/src/asterisk/asterisk-1.4.26/include/asterisk/strings.h:36
#19 0x006a4462 in realtime_exec (chan=0x892b988, context=0x892bb08 "default", exten=0x892bb58 "13671", priority=2, callerid=0x872f388 "0703181010", 
    data=0x85eff15 "@") at pbx_realtime.c:216
#20 0x080caae8 in pbx_extension_helper (c=0x892b988, con=Variable "con" is not available.
) at pbx.c:1874
#21 0x080cf246 in __ast_pbx_run (c=0x892b988) at pbx.c:2283
#22 0x080d118e in pbx_thread (data=0x892b988) at pbx.c:2599
#23 0x08102755 in dummy_start (data=0x0) at utils.c:856
#24 0x00d653cc in start_thread () from /lib/tls/libpthread.so.0
#25 0x00ccf96e in clone () from /lib/tls/libc.so.6
(gdb) frame 6
#6  0x009556cb in wav_read (s=0x8701538, whennext=0xd30804) at format_wav.c:378
378             if ( (res = fread(s->fr.data, 1, s->fr.datalen, s->f)) <= 0 ) {
(gdb) print s
$1 = (struct ast_filestream *) 0x8701538
(gdb) print *s
$2 = {fmt = 0x86af970, flags = 0, mode = 0, filename = 0x0, realfilename = 0x0, vfs = 0x0, trans = 0x0, tr = 0x0, lastwriteformat = 0, 
  lasttimeout = 160, owner = 0x87f36e8, f = 0x8849af0, fr = {frametype = AST_FRAME_VOICE, subclass = 64, datalen = 320, samples = 160, mallocd = 0, 
    mallocd_hdr_len = 0, offset = 64, src = 0x86af970 "wav", data = 0x87015f4, delivery = {tv_sec = 0, tv_usec = 0}, frame_list = {next = 0x0}, 
    flags = 0, ts = 0, len = 0, seqno = 0}, buf = 0x87015b4 "", {_private = 0x8701734, private = 0x8701734}, orig_chan_name = 0x0}