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c++ubuntuoverwritecoredump

C++: How to make "core" dump file being overwritten when new crash is encountered?

I got a simple c program to test "core dump" behavior:

$ cat 1.c

int main() 
{ 
   int buf[]={1,2}; 
   int j=buf[20000]+buf[30000]; 
   return 0; 
}

I did:

$ ulimit -c unlimited 
$ gcc 1.c 
$ a.out

It generates a core file, no problem. I run "a.out" again, this time the previous "core" file was not overwritten, unless I removed the core file manually, and then a new core file is generated.

Question: how can I setup the ubuntu linux to make sure each time there's a crash, a new core dump file will overwrite the old one?

Solution

  • You can toggle adding pid to core file, so every time program started with new pid core name will have new pid as 'extension'

    echo 1 > /proc/sys/kernel/core_uses_pid

    also, read this with much more details