How about ensuring that a "limit" won't be gone over?
bash and ksh have a builtin "ulimit" ksh, for example allows you to specify the max possible core size
Code:
ulimit -c <max core size>
on a per process basis.
The size command gives the amount of space the image file (executable) will use
when it is run. If there is a lot of dynamic memory allocation it will not show up.
try: man size
Plus, production code should NOT be dumping core. That is an awful idea. If the code is dumping because of SIGBUS or SIGSEGV, you need to fix it, not allocate more core space. If some admin is terminating the process and forcing core dumps, you might want to look at adopting different procedures.
Hi All
I am new for this forum. I have a core file by using gdb and bt cmd I got the function name but I want to the exact cause of the core dump because of I can not reproduse the binary so if any one know the cmd plz plz plz let me know. (0 Replies)
by what name does a core dump file stored???
like i wrote a test code:
//dump.c
main()
{
char *p=NULL;
printf("%s",p);
}
of course the above code will produce a segmentation fault. but i cant see any file named core in my CWD. am using SUN0S 5.9 (6 Replies)
Hi All,
May be it is a stupid question, but, I would like to know what is the advantage using a core dump file at the moment of debugging using gdb.
I know a core dump has information about the state of the application when it crashed, but, what is the difference between debugging using the... (2 Replies)
how to view core dumped file using gdb and how to extract information from the coredumped file.can we get similar information from the other utilites like strace or ptrace. (2 Replies)
Segmentation fault(core dumped)
but I cant find core file any where. how to make it out?
I try the command:ulimit -c unlimited, I even added it to the .bashrc file.And I removed ulimit setting in /etc/init.d/function. And there's no ulimit setting in /etc/profile. And I tried sudo find /... (8 Replies)
Hi Guys,
I was wondering if somebody could give me a link to a very good source of information or document about core dump process and How to's about it. I have also googled it and found some articles myself.
Thanks
Messi (1 Reply)
Hi,
I have got core dump stating "core.bash.29846" so i am unable to open.
How to open the core dump file for further analysis?
Reagards
Vanitha (7 Replies)
I am new to UNIX.
My Application is using c (.so files) and Java code.
My application crashes and CORE DUMP file is generated ,which is huge.
Now I want to view the CORE DUMP file to debug the application using dbx without starting process again.
By only using the CORE DUMP file and dbx ,can i... (1 Reply)
Discussion started by: satde
1 Replies
LEARN ABOUT ULTRIX
savecore
savecore(8) System Manager's Manual savecore(8)Name
savecore - save a core dump of the operating system
Syntax
/etc/savecore [ options ] dirname [ system ] [ corename ]
Description
The command is meant to be called near the end of the file. The command saves the core dump of the system (assuming one was made) and
writes a reboot message in the shutdown log.
The command checks the core dump to be certain it corresponds with the current running ULTRIX. If it does, it saves the core image in the
file dirname/vmcore.n and saves the namelist in the file dirname/vmunix.n. The trailing .n in the pathnames is replaced by a number which
increments each time is run in that directory.
After saving the core and namelist images, will save the error logger buffer into a predetermined file. The error logger buffer contains
information about why the crash occurred. After completes, the daemon will extract the error logger file and translate its contents into a
form familiar to the program.
Before writes out a core image, it reads a number from the file dirname/minfree. If there are fewer free blocks on the filesystem that
contains dirname than the number obtained from the file, a core dump is not done. If the file does not exist, savecore always writes out
the core file (assuming that a core dump was taken).
The command also writes a reboot message in the shut down log. If the system crashed as a result of a panic, also records the panic string
in the shut down log.
For partial crash dumps, creates a sparse core image file in dirname/vmcore.n. If this sparse core image file is copied or moved to
another location, the file expands to its true size which can take too much file system space. Hence, to copy or move sparse core image
files, you must use the command. The command has a conversion option to create sparse output files.
Options-c Clears the core dump. This option is useful when the core dump is corrupted in a way that will not allow to save it safely. Use the
option with caution, because once it clears the core dump, the core dump cannot be retrieved.
-d dumpdev dumplo
Specifies the dump device and the dump offset when running on a system image other than the currently running system image. The pro-
gram assumes that the running system image is and it reads the dump device and dump device offset are different in the system image
that crashed, the option provides the correct dump device and dump device offset.
-e Saves only the error logger buffer into a file. If used, core or namelist images are not saved.
-f corename
Takes the i corefile name as the file from which to extract the the crash dump data instead of the default dump device. This option
is used only for diskless workstations.
If the core dump was from a system other than /vmunix, the name of that system must be supplied as system. The program assumes that the
running image is
After successful completion, the core dump is cleared. Also, a message is written in the file which tells whether the dump succeeded or
failed.
Files
Shut down log
Current running ULTRIX system
See Alsodd(1), uerf(8)savecore(8)