Re^3: How to access the contents of a specific memory address?

Strange: When I try this, I get a segmentation fault. Am I overlooking some important detail?

$ perl -e 'print unpack("p", pack("J", 1))'
Segmentation fault
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Re^4: How to access the contents of a specific memory address? by Your Mother (Archbishop) on Jul 29, 2012 at 23:10 UTC
Am I overlooking some important detail? Simple logic. :P `Proposition: You can't get segfaults with pure Perl. Response: I disagree: code sample` [download]	[reply] [d/l]
Re^5: How to access the contents of a specific memory address? by pat_mc (Pilgrim) on Jul 30, 2012 at 19:12 UTC
Not sure I am finding your response very helpful. At any rate I'll pass your comment on to my bash shell that generated the output I quoted. Why can't Perl give rise to a segmentation fault? And what then is the meaning of the system output the given line of code produces?	[reply]
Re^6: How to access the contents of a specific memory address? by bulk88 (Priest) on Jul 30, 2012 at 20:26 UTC
You are asking why does null pointer (or something near null pointer such as memory address 1), causes a segmentation fault. It is that way because null pointer has caused segmentation fault since the begin of computers in the 20th century, decades ago ( see http://en.wikipedia.org/wiki/Segmentation_fault and http://en.wikipedia.org/wiki/Null_pointer#Null_pointer). You may be also asking, why does an example that is intended to crash the perl interp crash the perl interp. The answer to that is, because it is an example to crash the perl interp. A different question is, why does the perl interp crash from that example, read my second sentence.	[reply]