[root@tellus ~]# gdb /usr/sbin/asterisk
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This GDB was configured as "x86_64-unknown-linux-gnu"...Using host libthread_db library "/lib64/tls/libthread_db.so.1".

(gdb) bt
No stack.
(gdb) se
search        section       select-frame  set
(gdb) set breakpoint
(gdb) run
Starting program: /usr/sbin/asterisk
[Thread debugging using libthread_db enabled]
[New Thread 48005112096768 (LWP 3660)]
Asterisk already running on /var/run/asterisk.ctl.  Use 'asterisk -r' to connect.

Program exited with code 01.
(gdb) b
backtrace  break      bt
(gdb) b main
Breakpoint 1 at 0x470290: file asterisk.c, line 2035.
(gdb) run
Starting program: /usr/sbin/asterisk
[Thread debugging using libthread_db enabled]
[New Thread 47952089307136 (LWP 3668)]
[Switching to Thread 47952089307136 (LWP 3668)]

Breakpoint 1, main (argc=-1240222784, argv=0x4ab9b0) at asterisk.c:2035
2035    {
(gdb) bt
#0  main (argc=-1240222784, argv=0x4ab9b0) at asterisk.c:2035
(gdb)