SunOS man pages : core (4)
File Formats core(4)
NAME
core - core image file
DESCRIPTION
The operating system writes out a core image of a process
when it is terminated due to the receipt of some 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. This is also true for a process with an effective
group ID different from the real group ID. Set-user-ID and
set-group-ID programs do not produce core images either when
they terminate, since this would cause a security loophole.
The core file contains all the process information pertinent
to debugging: contents of hardware registers, process
status, and process data. The format of a core file is
object file specific.
For ELF executable programs (see a.out(4)), the core file
generated is also an ELF file, containing ELF program and
file headers. The e_type field in the file header has type
ET_CORE. The program header contains an entry for every seg-
ment that was part of the process address space, including
shared library segments. The contents of the writable seg-
ments are also part of the core image.
The program header of an ELF core file also contains entries
for two NOTE segments, each containing several note entries
as described below. The note entry header and core file note
type (n_type) definitions are contained in <sys/elf.h>. The
first NOTE segment exists for binary compatibility with old
programs that deal with core files. It contains structures
defined in <sys/old_procfs.h>. New programs should recognize
and skip this NOTE segment, advancing instead to the new
NOTE segment. The old NOTE segment will be deleted from core
files in a future release.
The old NOTE segment contains the following entries. Each
has entry name "CORE" and presents the contents of a system
structure:
prpsinfo_t
n_type : NT_PRPSINFO. This entry contains information
of interest to the ps(1) command, such as process
status, CPU usage, "nice" value, controlling terminal,
user-ID, process-ID, the name of the executable, and
so forth. The prpsinfo_t structure is defined in
<sys/old_procfs.h>.
char array
SunOS 5.8 Last change: 14 Jul 1999 1
File Formats core(4)
n_type: NT_PLATFORM. This entry contains a string
describing the specific model of the hardware platform
on which this core file was created. This information
is the same as provided by sysinfo(2) when invoked
with the command SI_PLATFORM.
auxv_t array
n_type: NT_AUXV. This entry contains the array of
auxv_t structures that was passed by the operating
system as startup information to the dynamic linker.
Auxiliary vector information is defined in
<sys/auxv.h>.
Following these entries, for each light-weight process (LWP)
in the process, the old NOTE segment contains an entry with
a prstatus_t structure, plus other optionally-present
entries describing the LWP, as follows:
prstatus_t
n_type: NT_PRSTATUS. This structure contains things of
interest to a debugger from the operating system, such
as the general registers, signal dispositions, state,
reason for stopping, process-ID, and so forth. The
prstatus_t structure is defined in <sys/old_procfs.h>.
prfpregset_t
n_type: NT_PRFPREG. This entry is present only if the
LWP used the floating-point hardware. It contains the
floating-point registers. The prfpregset_t structure
is defined in <sys/procfs_isa.h>.
gwindows_t
n_type: NT_GWINDOWS. This entry is present only on a
SPARC machine and only if the system was unable to
flush all of the register windows to the stack. It
contains all of the unspilled register windows. The
gwindows_t structure is defined in <sys/regset.h>.
prxregset_t
n_type: NT_PRXREG. This entry is present only if the
machine has extra register state associated with it.
It contains the extra register state. The prxregset_t
structure is defined in <sys/procfs_isa.h>.
The new NOTE segment contains the following entries. Each
has entry name "CORE" and presents the contents of a system
structure:
psinfo_t
n_type: NT_PSINFO. This structure contains information
of interest to the ps(1) command, such as process
status, CPU usage, "nice" value, controlling terminal,
SunOS 5.8 Last change: 14 Jul 1999 2
File Formats core(4)
user-ID, process-ID, the name of the executable, and
so forth. The psinfo_t structure is defined in
<sys/procfs.h>.
pstatus_t
n_type: NT_PSTATUS. This structure contains things of
interest to a debugger from the operating system, such
as pending signals, state, process-ID, and so forth.
The pstatus_t structure is defined in <sys/procfs.h>.
char array
n_type: NT_PLATFORM. This entry contains a string
describing the specific model of the hardware platform
on which this core file was created. This information
is the same as provided by sysinfo(2) when invoked
with the command SI_PLATFORM.
auxv_t array
n_type: NT_AUXV. This entry contains the array of
auxv_t structures that was passed by the operating
system as startup information to the dynamic linker.
Auxiliary vector information is defined in
<sys/auxv.h>.
struct utsname
n_type: NT_UTSNAME. This structure contains the system
information that would have been returned to the pro-
cess if it had performed a uname(2) system call prior
to dumping core. The utsname structure is defined in
<sys/utsname.h>.
prcred_t
n_type: NT_PRCRED. This structure contains the process
credentials, including the real, saved, and effective
user and group IDs. The prcred_t structure is defined
in <sys/procfs.h>. Following the structure is an
optional array of supplementary group IDs. The total
number of supplementary group IDs is given by the
pr_ngroups member of the prcred_t structure, and the
structure includes space for one supplementary group.
If pr_ngroups is greater than 1, there will be
pr_ngroups - 1 gid_t items following the structure;
otherwise, there will be no additional data.
Following these entries, for each LWP in the process, the
new NOTE segment contains an entry with an lwpsinfo_t struc-
ture plus an entry with an lwpstatus_t structure, plus other
optionally-present entries describing the LWP, as follows:
lwpsinfo_t
n_type: NT_LWPSINFO. This structure contains
SunOS 5.8 Last change: 14 Jul 1999 3
File Formats core(4)
information of interest to the ps(1) command, such as
LWP status, CPU usage, "nice" value, LWP-ID, and so
forth. The lwpsinfo_t structure is defined in
<sys/procfs.h>.
lwpstatus_t
n_type: NT_LWPSTATUS. This structure contains things
of interest to a debugger from the operating system,
such as the general registers, the floating point
registers, state, reason for stopping, LWP-ID, and so
forth. The lwpstatus_t structure is defined in
<sys/procfs.h>.
gwindows_t
n_type: NT_GWINDOWS. This entry is present only on a
SPARC machine and only if the system was unable to
flush all of the register windows to the stack. It
contains all of the unspilled register windows. The
gwindows_t structure is defined in <sys/regset.h>.
prxregset_t
n_type: NT_PRXREG. This entry is present only if the
machine has extra register state associated with it.
It contains the extra register state. The prxregset_t
structure is defined in <sys/procfs_isa.h>.
asrset_t
n_type: NT_ASRS. This entry is present only on a SPARC
V9 machine and only if the process is a 64-bit pro-
cess. It contains the ancillary state registers for
the LWP. The asrset_t structure is defined in
<sys/regset.h>.
The size of the core file created by a process may be con-
trolled by the user (see getrlimit(2)).
SEE ALSO
adb(1), gcore(1), ps(1), crash(1M), getrlimit(2), setuid(2),
sysinfo(2), uname(2), elf(3ELF), a.out(4), proc(4),
signal(3HEAD)
ANSI C Programmer's Guide
SunOS 5.8 Last change: 14 Jul 1999 4
|
 |
|
|
