Using gdb on a root process

Dear experts,
I am trying to attach a root process to gdb debugger.

What i did:

  • I opened a root in a terminal
  • in another terminal, i found the id of the root.exe with $pidof root.exe (gives 12345)
    and attached it to the gdb with: $sudo gdb -p 12345.

My problem is that it does not agttach the root.exe process, ending up with this error instead:

0x00007faef4288faa in __GI___select (nfds=1, readfds=0x4cf580, writefds=0x4cf610, exceptfds=exceptfds@entry=0x0, timeout=timeout@entry=0x0) at …/sysdeps/unix/sysv/linux/select.c:41
41 …/sysdeps/unix/sysv/linux/select.c: No such file or directory.

Do you know what can I do in order to attached root.exe successfully, or what am I doing wrong?

That’s fine, I think. Your “root.exe” is waiting for the user’s input in the standard glibc function (and you do not have the source code of this library “installed”, of course).