memory

问题 A process is terminated successfully or abnormally on some OS, when does an OS decide to wipe out the memory (data, code etc.) allocated to that process; at exit or when it wants to allocate memory to a new process? And is this wiping out memory allocation procedure the same on all operating systems (winXP, Win7, linux, Mac)? I understand, page table has mapping of virtual addresses for that process and actual physical addresses in the memory. Thanks. 回答1: How an OS reclaims process resources

问题 A process is terminated successfully or abnormally on some OS, when does an OS decide to wipe out the memory (data, code etc.) allocated to that process; at exit or when it wants to allocate memory to a new process? And is this wiping out memory allocation procedure the same on all operating systems (winXP, Win7, linux, Mac)? I understand, page table has mapping of virtual addresses for that process and actual physical addresses in the memory. Thanks. 回答1: How an OS reclaims process resources

问题 How do I determine the size of my array in C? That is, the number of elements the array can hold? 回答1: Executive summary: int a[17]; size_t n = sizeof(a)/sizeof(a[0]); Full answer: To determine the size of your array in bytes, you can use the sizeof operator: int a[17]; size_t n = sizeof(a); On my computer, ints are 4 bytes long, so n is 68. To determine the number of elements in the array, we can divide the total size of the array by the size of the array element. You could do this with the

问题 How do I determine the size of my array in C? That is, the number of elements the array can hold? 回答1: Executive summary: int a[17]; size_t n = sizeof(a)/sizeof(a[0]); Full answer: To determine the size of your array in bytes, you can use the sizeof operator: int a[17]; size_t n = sizeof(a); On my computer, ints are 4 bytes long, so n is 68. To determine the number of elements in the array, we can divide the total size of the array by the size of the array element. You could do this with the

问题 How do I determine the size of my array in C? That is, the number of elements the array can hold? 回答1: Executive summary: int a[17]; size_t n = sizeof(a)/sizeof(a[0]); Full answer: To determine the size of your array in bytes, you can use the sizeof operator: int a[17]; size_t n = sizeof(a); On my computer, ints are 4 bytes long, so n is 68. To determine the number of elements in the array, we can divide the total size of the array by the size of the array element. You could do this with the

问题 I have recently started working on an Android project with native calls via JNI. I've learnt about pretty restrictive limitations regarding number of references a native call can create. I would like to understand deeply how this reference management works. I studied some information but I still have a few questions that I would like to know the answers to. Without further ado: Which kinds of references in native code can cause those memory limits to be exceeded? Which count towards limits

问题 I have recently started working on an Android project with native calls via JNI. I've learnt about pretty restrictive limitations regarding number of references a native call can create. I would like to understand deeply how this reference management works. I studied some information but I still have a few questions that I would like to know the answers to. Without further ado: Which kinds of references in native code can cause those memory limits to be exceeded? Which count towards limits

问题 I would like to use ptrace in order to attach my tool to a Linux process, read and write to the heap memory of this process and again detach my tool. Actually, it's not working although there is no error. I can not see any modifications in the heap memory of the process after I run the tool. Anyway, I'm quite not sure if that is possible in general. Currently, my C code looks like this: int res = 0, i = 0; int size = heap_address->end - heap_address->start; char tmp_page[size]; memset(tmp

问题 I would like to use ptrace in order to attach my tool to a Linux process, read and write to the heap memory of this process and again detach my tool. Actually, it's not working although there is no error. I can not see any modifications in the heap memory of the process after I run the tool. Anyway, I'm quite not sure if that is possible in general. Currently, my C code looks like this: int res = 0, i = 0; int size = heap_address->end - heap_address->start; char tmp_page[size]; memset(tmp

问题 I would like to use ptrace in order to attach my tool to a Linux process, read and write to the heap memory of this process and again detach my tool. Actually, it's not working although there is no error. I can not see any modifications in the heap memory of the process after I run the tool. Anyway, I'm quite not sure if that is possible in general. Currently, my C code looks like this: int res = 0, i = 0; int size = heap_address->end - heap_address->start; char tmp_page[size]; memset(tmp