In my experience, a bus error is caused by the same type of problem as a segmentation fault (i.e. out of bounds memory access). I once had an out of bounds memory access in a program I wrote and found that depending on how far out of bounds my access was, the error message would change between "segmentation fault" and "bus error" (this program was running under Solaris on a Sun machine).
I'm not certain why one message appears sometimes and the other at other times, but one possibility (a wild guess) is that since some architectures use part of the address space to represent IO devices instead of memory locations, the "Bus Error" message will occur if the illegal memory location falls in the IO device address range and a "Segmentation Fault" will occur if the illegal memory location falls in the memory range. FWIW, I've never seen a bus error message on x86 Linux, so maybe it doesn't happen on the x86 architecture or maybe it's just triggered differently. Matt On Mon, Jan 07, 2002 at 04:18:57PM -0800, Peter Jay Salzman wrote: > i did a google search, and found alot of conflicting answers. some of > them seemed to indicate that the precise definition of bus error is > architecture dependent, but i find that hard to believe. > > i know what a segmentation violation is. > > but what exactly is a bus error? > > can anyone write a hello world type program that demonstrates barfing > from a bus error? i found some code that purported to produce a bus > error on a sparc, but it didn't barf under linux. > > pete > > -- > PGP Fingerprint: B9F1 6CF3 47C4 7CD8 D33E 70A9 A3B9 1945 67EA 951D > PGP Public Key: finger [EMAIL PROTECTED] > _______________________________________________ > vox-tech mailing list > [EMAIL PROTECTED] > http://lists.lugod.org/mailman/listinfo/vox-tech -- ************************************************* * Matt Roper <[EMAIL PROTECTED]> * * http://www.mattrope.com * * PGP Key: http://www.mattrope.com/mattrope.asc * ************************************************* _______________________________________________ vox-tech mailing list [EMAIL PROTECTED] http://lists.lugod.org/mailman/listinfo/vox-tech
