When a segmentation fault occurs in Linux, the error message Segmentation fault (core dumped) will be printed to the terminal (if any), and the program will be terminated. As a C/C++ dev, this happens to me quite often, and I usually ignore it and move onto gdb, recreating my previous action in order to trigger the invalid memory reference again. Instead, I thought I might be able to perhaps use this core instead, as running gdb all the time is rather tedious, and I cannot always recreate the segmentation fault.My questions are three:Where is this elusive core dumped?What does it contain?What can I do with it?
Segmentation fault (core dumped) - to where? what is it? and why?
segmentation fault;core dump
If other people clean up ...... you usually don't find nothing. But luckily Linux has a handler for this which you can specify at runtime. In /usr/src/linux/Documentation/sysctl/kernel.txt you will find:[/proc/sys/kernel/]core_pattern is used to specify a core dumpfile pattern name.If the first character of the pattern is a '|', the kernel will treat  the rest of the pattern as a command to run.  The core dump will be  written to the standard input of that program instead of to a file.(thanks)According to the source this is handled by the abrt program (that's Automatic Bug Reporting Tool, not abort), but on my Arch Linux it is handled by systemd. You may want to write your own handler or use the current directory.But what's in there?Now what it contains is system specific, but according to the all knowing encyclopedia:[A core dump] consists of the recorded state of the working memory of a computer  program at a specific time[...]. In practice, other key pieces of  program state are usually dumped at the same time, including the  processor registers, which may include the program counter and stack  pointer, memory management information, and other processor and  operating system flags and information.... so it basically contains everything gdb ever wanted, and more.Yeah, but I'd like me to be happy instead of gdbYou can both be happy since gdb will load any core dump as long as you have a exact copy of your executable: gdb path/to/binary my/core.dump. You should then be able to continue business as usual and be annoyed by trying and failing to fix bugs instead of trying and failing to reproduce bugs.