How can I still get my core dump when I run something from cron which would normally core?
For a core file to be generated on a crash, core dumps must be enabled in the current environment. From a shell, this can be done using ulimit:
ulimit -c unlimitedWhich means "set the maximum core dump size to unlimited". Your system is probably configured to do this in interactive shells, but not in cron jobs. To do it from a cron job, you need to modify this limit. If the cron job is a shell script which calls other programs, you can just call ulimit as above. On the other hand, if the job is an executable, you can create a wrapper to run it with:
#!/bin/bashulimit -c unlimitedexec "$@"Another option is to modify the program to set the limit itself using the setrlimit function.
As to why your cores are going in /cores as opposed to the working directory: your distribution may have adjusted the core pattern, possibly using a program to handle core files and place them in /cores.