core(4)                                                   core(4)



     NAME
          core - format of core image file

     DESCRIPTION
          The Oreo System writes out a core image of a terminated
          process when any of various errors occur.  See signal(3) for
          the list of reasons; the most common are memory violations,
          illegal instructions, bus errors, and user-generated quit
          signals.  The core image is called core and is written in
          the process's working directory (provided it can be; normal
          access controls apply).  A process with an effective user ID
          different from the real user ID will not produce a core
          image.

          The first section of the core image is a copy of the
          system's per-user data for the process, including the
          registers as they were at the time of the fault.  The size
          of this section depends on the parameter USIZE, which is
          defined in /usr/include/sys/param.h.  The remainder
          represents the actual contents of the user's core area when
          the core image was written.  If the text segment is read-
          only and shared, or separated from data space, it is not
          dumped.

          The format of the information in the first section is
          described by the user structure of the system, defined in
          /usr/include/sys/user.h.  The important stuff not detailed
          therein is the locations of the registers, which are
          outlined in /usr/include/sys/reg.h.

     SEE ALSO
          setuid(2), signal(3).























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