Enable strace for docker container

[huan]

上帝说，要有光。于是就有了光。

KCN: 方便动态调试，docker启动需要允许strace

docker run --cap-add=SYS_PTRACE  ...

Links

• 如何在Docker容器内部使用gdb进行debug
• Why strace doesn't work in Docker
• https://github.com/moby/moby/issues/21051#issuecomment-325036902

[huan]

Online system updated, it seems to work now:

bbs@bbs:~$ gdb /kbs/bin/bbsd 
GNU gdb (Debian 7.7.1+dfsg-5) 7.7.1
Copyright (C) 2014 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-linux-gnu".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
<http://www.gnu.org/software/gdb/documentation/>.
For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from /kbs/bin/bbsd...done.
(gdb) r
Starting program: /kbs/bin/bbsd 
warning: Error disabling address space randomization: Operation not permitted
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Inferior 1 (process 310) exited normally]
(gdb) b main
Breakpoint 1 at 0x412850: file bbsd_single.c, line 673.
(gdb) r
Starting program: /kbs/bin/bbsd 
warning: Error disabling address space randomization: Operation not permitted
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".

Breakpoint 1, main (argc=1, argv=0x7ffd18f648e8) at bbsd_single.c:673
673	bbsd_single.c: No such file or directory.
(gdb) l
668	in bbsd_single.c
(gdb) n
676	in bbsd_single.c
(gdb) n
673	in bbsd_single.c
(gdb) n
676	in bbsd_single.c
(gdb) n
673	in bbsd_single.c
(gdb)