C Bus Error Core Dumped
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Bus Error Core Dumped Linux
Join the Stack Overflow Community Stack Overflow is a community of 4.7 million programmers, just like you, helping each other. Join them; it only bus error linux takes a minute: Sign up What is a bus error? up vote 155 down vote favorite 49 What does the "bus error" message mean, and how does it differ from a segfault? c unix segmentation-fault bus-error share|improve this question edited Oct bus error (core dumped) centos 18 '15 at 10:44 Cool Guy 15.8k51952 asked Oct 17 '08 at 14:48 raldi 7,239216178 add a comment| 15 Answers 15 active oldest votes up vote 150 down vote accepted Bus errors are rare nowadays on x86 and occur when your processor cannot even attempt the memory access requested, typically: using a processor instruction with an address that does not satisfy its alignment requirements. Segmentation faults occur when accessing memory which does not belong to your process, they are very common
How To Debug Bus Error
and are typically the result of: using a pointer to something that was deallocated. using an uninitialized hence bogus pointer. using a null pointer. overflowing a buffer. PS: To be more precise this is not manipulating the pointer itself that will cause issues, it's accessing the memory it points to (dereferencing). share|improve this answer edited Oct 17 '08 at 15:18 answered Oct 17 '08 at 15:12 bltxd 5,70322336 52 They aren't rare; I'm just at Exercise 9 from How to Learn C the Hard Way and already encountered one... –11684 Mar 26 '13 at 20:12 5 Another cause of bus errors (on Linux anyway) is when the operating system can't back a virtual page with physical memory (e.g. low-memory conditions or out of huge pages when using huge page memory.) Typically mmap (and malloc) just reserve the virtual address space, and the kernel assigns the physical memory on demand (so called soft page faults.) Make a large enough malloc, and then write to enough of it and you'll get a bus error. –Eloff Jul 14 '15 at 0:09 add a comment| up vote 55 down vote A segfault is accessing memory that you're not allowed to access. It's read-only, you don't have permission, etc... A bus error is trying to access memory that can't possibly be there. You've used an address that's meaningless to the system, or the wrong kind of address for that operation. share|improve this answer answere
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How To Solve Bus Error In Linux
Stack Overflow Community Stack Overflow is a community of 4.7 million programmers, just like you, helping each other. Join them; it only takes a minute: Sign up Bus error vs Segmentation fault up http://stackoverflow.com/questions/212466/what-is-a-bus-error vote 25 down vote favorite 8 Difference between a bus error and a segmentation fault? Can it happen that a program gives a seg fault and stops for the first time and for the second time it may give a bus error and exit ? c share|improve this question edited May 2 '12 at 12:04 casperOne 58k10126202 asked May 8 '09 at 6:56 Thunderboltz 6253915 add http://stackoverflow.com/questions/838540/bus-error-vs-segmentation-fault a comment| 6 Answers 6 active oldest votes up vote 34 down vote accepted On most architectures I've used, the distinction is that: a SEGV is caused when you access memory you're not meant to (e.g., outside of your address space). a SIGBUS is caused due to alignment issues with the CPU (e.g., trying to read a long from an address which isn't a multiple of 4). share|improve this answer answered May 8 '09 at 7:06 paxdiablo 488k1179691416 10 Memory mapped files can also generate SIGBUS. –bk1e May 8 '09 at 16:06 on arm SIGBUS can occur if you read a float from an address that is not 4 byte aligned –shoosh Mar 30 at 7:29 shoosh, I'm pretty certain that's covered by my second bullet point. –paxdiablo Mar 30 at 13:28 add a comment| up vote 11 down vote SIGBUS will also be raised if you mmap() a file and attempt to access part of the mapped buffer that extends past the end of the file, as well as for error conditions such as out of space. If you register a signal handler using sigaction() and you set SA_SIGINFO,
Search Username Password Remember Me? Register Lost Password? facebook google twitter rss Free Web Developer Tools Advanced Search Forum Programming Languages C Programming difference between seg fault core dump bus error Thread: difference between seg fault core dump bus error Share This Thread Tweet This + 1 this Post To Linkedin Subscribe to this Thread Subscribe to This Thread August 14th, 2004,01:16 PM #1 No Profile Picture Technical View Profile View Forum Posts Registered User Devshed Newbie (0 - 499 posts) Join Date Aug 2004 Posts 1 Rep Power 0 difference between seg fault core dump bus error Hello C experts, Can I have 3 programs for producing the following errors ? 1. Segmentation fault 2. Core dump 3. Bus error I guess to get case one, *p='a' where p has not been allocated memory will do. How about the others ? Thanks in advance. Faq Reply With Quote August 14th, 2004,01:33 PM #2 DaWei_M View Profile View Forum Posts Visit Homepage Lord of Dorkness Devshed Supreme Being (6500+ posts) Join Date Jan 2004 Location Central New York. Texan via Arizona, out of his element! Posts 8,524 Rep Power 3316 1. Segmentation fault. Attempting to access memory in a segment one isn't allowed to access. 2. Core dump. Typically, an error which causes the OS to dump some contents of memory for trace purposes (often the stack). 'Core' was originally a memory technology which consisted of ferrite (magnetic) toroids with windings to set their direction of magnetization and a sense winding to read the current direction of magnetization. It generally just refers to any memory nowadays. The last core I used was a 256K module about 6 x 10 inches occupying the width of a couple PCI slots in today's PCs. 3. Bus Error. The most common cause is an invalid address alignment reference, although attempting to access a non-existent item at a particular bus address can also produce the fault. EDIT: Core in the original sense is non-volatile. It retains its contents when power is off, like CMOS, but doesn't need a battery. Put your OS in there, voila, no boot required! :D Last edited by DaWei_M; August 14th, 2004 at 02:01 PM. Functionality rules and clarity matters; if you can work a little elegance in there, you're stylin'. If you can't spell "u", "ur", and "ne1", why would I hire you? 300 b