对使用attach命令.查看this link了解更多信息.在GDB控制台上键入help attach可提供以下信息:
(gdb) help attach附加到GDB之外的进程或文件.
注意:由于improved security in the Linux kernel，您可能很难连接到进程，例如从一个shell 连接到另一个shell 的子shell .
根据您的要求，您可能需要设置/proc/sys/kernel/yama/ptrace_scope.许多系统现在默认为1或更高.
The sysctl settings (writable only with CAP_SYS_PTRACE) are:
0 - classic ptrace permissions: a process can PTRACE_ATTACH to any other
process running under the same uid, as long as it is dumpable (i.e.
did not transition uids, start privileged, or have called
prctl(PR_SET_DUMPABLE...) already). Similarly, PTRACE_TRACEME is
unchanged.
1 - restricted ptrace: a process must have a predefined relationship
with the inferior it wants to call PTRACE_ATTACH on. By default,
this relationship is that of only its descendants when the above
classic criteria is also met. To change the relationship, an
inferior can call prctl(PR_SET_PTRACER, debugger, ...) to declare
an allowed debugger PID to call PTRACE_ATTACH on the inferior.
Using PTRACE_TRACEME is unchanged.
2 - admin-only attach: only processes with CAP_SYS_PTRACE may use ptrace
with PTRACE_ATTACH, or through children calling PTRACE_TRACEME.
3 - no attach: no processes may use ptrace with PTRACE_ATTACH nor via
PTRACE_TRACEME. Once set, this sysctl value cannot be changed.