HELP! Why do I get error message: "Segmentation fault(coredump)" ?

[Richard Stanton]

The following may be simple, but I'm new to the AIX environment (and to 
programming in C under any UNIX).

I am trying to run a large C program on an IBM RS/6000. The program has
run fine on a VAX, but when I try to run it on the IBM, it starts OK, but
after a certain point I get the error message:

"Segmentation fault(coredump)"

This appears to happen at a section of code where memory is being allocated
using calloc, but I test for failure here, and my own error message is never
produced. What does this error message mean, and what do I have to do to
get the program to run properly?

Another program dies at a similar point, but this time it tells me it can't
allocate the memory I asked for using my own error message. How can I increase
the amount of memory available to the program?

Thanks for any help you can give me.

Richard Stanton
pstanton at gsb-lira.stanford.edu