Berkeley CSUA MOTD:Entry 18795
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2025/07/08 [General] UID:1000 Activity:popular
7/8     

2000/7/27-29 [Computer/SW/Languages/C_Cplusplus, Computer/HW/Memory, Computer/SW/Unix] UID:18795 Activity:very high
7/27    Where can I find an explanation of what usually causes a core dump,
        bus error etc. ?
        \_ core dump = just that. core memory used to me a type of volatile
           storage which died out quick but the term still lives on (hence
                        \_ As opposed to current storage which dies out quick?
                           Get your story correct or don't try to sound leet.
                                \_ As opposed to current solid-state memory
                                   technology which has been used for decades.
                                   Get a clue before you flame.
        The point, which you missed utterly, is that "a type...  _/
        which died out quick" also describes modern memory, and neither
        distinguishes between core and solid-state nor accurately
        distinguishes between core and solid-state memory nor accurately
        explains why it was called core in the first place.  Twink.
                \_ modern memory technology has not died out slowly or quickly
                   it's still used all over the place.  No one has used core
                   memory in decades.  It doesn't explain why it was called
                   core, but does distinguish a short-lived, long-dead
                   technology from a long-lived, still-used technology
                   \_ Why are you talking about the technology and not
                      the storage itself?
     [a place for twinks on the web:  http://www.twinkparadise.com ]_/
           core dump, out of core, core map, etc...) core dumps are usually
           a result of an illegal operation and can be enabled and disabled.
           bus error = i think means misaligned address (obviously illegal).
           segmentation fault = there are only certain segments a user
           program can read and write from.  these access bits are usually
           written to the TLB and automatically cause an exception when you
           access a segment in a way you're not supposed to.
        \_ Get this book, it kicks ass:
           Peter van der Linden, Expert C Programming. ISBN 0131774298
        \_ you mean you want something more to know about getting a bus
           error because you are accessing memory which is "not valid"
           (note the quotes).
        \_ I was looking for an answer like "This happens when you dont
           allocate enough space to an array, or you look past the end of
           and array" etc.
                \_ accessing null pointers, accessing memory out of
                   bounds (reading past allocated memory), etc.
                   Its good idea to check a pointer's validity before
                   accessing it (like a->foo()).
                   \_ no, you can get core dumps from lots of uncatched
                      exceptoins. i don't have to deref NULL or an address
                      outside my addressspace to get a SIGABRT for example
                      (which coredumps).
                      \_ true but the original poster probably wanted to know
                         common reasons.
                         \_ Yes, Thank You.  Now what is a Bus Error?
                                \_ As explained above, a bus error is caused
                                   by attempting to read an address/size your
                                   memory bus considers illegal, such as a
                                   32-bit word at an odd address.  Usually
                                   caused by utter garbage in your pointers,
                                   due either to not initializing it or
                                   overwriting it with other data.
2025/07/08 [General] UID:1000 Activity:popular
7/8     

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