"Moreover, what exactly causes a segmentation fault?"

From the Jargon File:

segmentation fault n.

{Unix} 1. {techspeak} An error in which a running program attempts to access memory not allocated to it and core dumps with a segmentation violation error. This is often caused by improper usage of pointers in the source code, dereferencing a null pointer, or (in C) inadvertently using a non-pointer variable as a pointer. The classic example is:

   int i;
   scanf ("%d", i);  /* should have used &i */
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2. To lose a train of thought or a line of reasoning. Also uttered as an exclamation at the point of befuddlement.

redmist
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