core_uses_pid

file: /proc/sys/kernel/core_uses_pid
variable: kernel.core_uses_pid
Official reference

The default coredump filename is “core”. By setting core_uses_pid to 1, the coredump filename becomes core.PID. If core_pattern does not include “%p” (default does not) and core_uses_pid is set, then .PID will be appended to the filename.

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