Why does ppp(8) get a seg-fault, but I see no ppp.core file?

Ppp (or any other program for that matter) should never dump core. Because ppp(8) runs with an effective user id of 0, the operating system will not write ppp(8)'s core image to disk before terminating it. If, however ppp(8) is actually terminating due to a segmentation violation or some other signal that normally causes core to be dumped, and you are sure you are using the latest version (see the start of this section), then you should do the following:

    % tar xfz ppp-*.src.tar.gz
    % cd ppp*/ppp
    % echo STRIP= >>Makefile
    % echo CFLAGS+=-g >>Makefile
    % make clean all
    % su
    # make install
    # chmod 555 /usr/sbin/ppp

You will now have a debuggable version of ppp(8) installed. You will have to be root to run ppp(8) as all of its privileges have been revoked. When you start ppp(8), take a careful note of what your current directory was at the time.

Now, if and when ppp(8) receives the segmentation violation, it will dump a core file called ppp.core. You should then do the following:

    % su
    # gdb /usr/sbin/ppp ppp.core
    (gdb) bt
    (gdb) f 0
    (gdb) i args
    (gdb) l

All of this information should be given alongside your question, making it possible to diagnose the problem.

If you are familiar with gdb, you may wish to find out some other bits and pieces such as what actually caused the dump and the addresses & values of the relevant variables.

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