.
Thread 2 (Thread 2201):
#0  0x00615422 in __kernel_vsyscall ()
No symbol table info available.
#1  0x0032ab86 in poll () from /lib/tls/i686/cmov/libc.so.6
No symbol table info available.
#2  0x006fc2de in ?? () from /usr/lib/libavahi-common.so.3
No symbol table info available.
#3  0x006faa3d in avahi_simple_poll_run () from /usr/lib/libavahi-common.so.3
No symbol table info available.
#4  0x006fb2d0 in avahi_simple_poll_iterate ()
   from /usr/lib/libavahi-common.so.3
No symbol table info available.
#5  0x006fb320 in avahi_simple_poll_loop () from /usr/lib/libavahi-common.so.3
No symbol table info available.
#6  0x006fc0cb in ?? () from /usr/lib/libavahi-common.so.3
No symbol table info available.
#7  0x004b496e in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
No symbol table info available.
#8  0x00338a4e in clone () from /lib/tls/i686/cmov/libc.so.6
No symbol table info available.
.
Thread 1 (Thread 2200):
#0  gt68xx_line_reader_free_delays (reader=0x0) at gt68xx_mid.c:957
No locals.
#1  0x00de3589 in gt68xx_line_reader_free (reader=0x0) at gt68xx_mid.c:1153
        status = <value optimised out>
#2  0x00de3611 in gt68xx_scanner_stop_scan (scanner=0x9243128)
    at gt68xx_high.c:946
No locals.
#3  0x00de39c1 in sane_gt68xx_cancel (handle=0x9243128) at gt68xx.c:2108
No locals.
#4  0x0078519f in sane_dll_cancel (handle=0x922a348) at dll.c:1263
No locals.
#5  0x007837dd in sane_cancel (h=0x922a348) at dll-s.c:72
No locals.
#6  0x0804c2e7 in main (argc=2, argv=0xbfaf8234) at scanimage.c:2318
        n = 2
        ch = <value optimised out>
        i = <value optimised out>
        index = 2
        opt = <value optimised out>
        device_list = 0x9216f78
        num_dev_options = 25
        devname = 0x0
        defdevname = 0x5 <Address 0x5 out of bounds>
        format = 0x804ff1e "out%d.pnm"
        readbuf = "\000"
        readbuf2 = <value optimised out>
        batch = 1
        batch_prompt = 0
        batch_count = -1
        batch_start_at = 2
        batch_increment = 1
        status = SANE_STATUS_GOOD
        version_code = <value optimised out>