Can memcpy fail

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August undefined, 2024

WebMar 9, 2011 · I would like to know if it is guaranteed, by the standard, that memcpy (0,0,0) is safe. The only restriction I could find is that if the memory regions overlap, then the … WebJul 5, 2016 · I found a different way to write data, which is faster than normal unix write function. Firstly, ftruncate the file to the length we need, then mmap this block of file, finally, using memcpy to flush the file content. I will give the example code below. As I known, mmap can load the file into the process address space, accelerating by ignoring ...

c - Troubles with using memcpy with mmap - Stack Overflow

WebMay 24, 2010 · strcpy terminates when the source string's null terminator is found. memcpy requires a size parameter be passed. In the case you presented the printf statement is halting after the null terminator is found for both character arrays, however you will find t [3] and t [4] have copied data in them as well. Share Improve this answer Follow WebSep 6, 2011 · If you're on linux, memcpy is already very optimized, probably even too much so (I think we noticed a crash once with memcpy over a page border). That said, you're … how do people love themselves

C copy file with memcpy and mmap file to RAM - Stack Overflow

WebOct 30, 2012 · But the proper solution would be to use strcpy (), which copies the trailling null character automatically. Also, think to allocate memory for dest_data ( malloc ( (len + … WebIn truth, memcpy can not fail [obviously assuming correctly working hardware and not wacky arguments and it tries to read/write memory that it shouldn't be touching and … WebMar 28, 2013 · The compilation will fail if the condition isn't true, or can't be evaluated by the compiler. #define BUILD_ASSERT_OR_ZERO (cond) \ (sizeof (char [1 - 2*! (cond)]) - 1) … how do people lose weight so fast

Disagreement about memcpy - C++ Programming

c - failure scenarios for memcpy - Stack Overflow

WebAug 18, 2015 · Using Clang on ARM target, memcpy works fine (see @notlikethat comment below). It would be easy to blame GCC at large, but it's not that simple : the memcpy solution works fine on GCC with x86/x64, PPC and ARM64 targets. WebNov 7, 2014 · buffer = malloc ( sizeof *cpy ); memcpy (buffer, cpy, sizeof *cpy ); There is a possible problem with this code though. The struct might contain padding. (Typically it … how do people maintain homeostasisWebAug 20, 2013 · The answer is: "you can't". The pointer is not where the string data is stored. The string data is stored elsewhere in memory... and your pointer simply points to the … how much rain does the desert get

"WebJan 10, 2024 · memcpy ( data, &buff [2], 3u ) ; Both the pointer arithmetic and casts are unnecessary and contrary to MISRA rules. To cast to a void* rather misunderstands the … " - Can memcpy fail

Can memcpy fail

c++ - Replacing memcpy in a safe way - Stack Overflow

WebMay 5, 2024 · Using memset () is slower, except when -O3 is used, then the failing -O3 is somewhat compensated by the use of memset. The -O and -O2 are of course better for speed than the default Arduino -Os for size. For the compiler flags, I used the #pragma #pragma GCC optimize ("-O3") Koepel June 12, 2024, 10:51pm #11 These are the … WebOct 8, 2011 · is ok, because "123" is allocated at compile time, so data->data points to beginning of string "123", but calling memcpy (data->data,"123",4) will fail, because pointer to data-data is uninitialised and point to some random location in memory that can not be even read. Share Improve this answer Follow edited Oct 8, 2011 at 17:27

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WebApr 10, 2024 · GCC Bugzilla – Bug 109465 LoongArch: The expansion of memcpy is slow and bloated for some sizes Last modified: 2024-04-13 07:42:48 UTC WebOct 13, 2015 · However, I can't seem to use memcpy to do the equivalent copy. This only manages to copy the first element: double data_memcopy [9]; memcpy …

WebJun 16, 2024 · GPU->CPU Memcpy failed Error or InternalError c2c fft failed Error when using FFT2D #10759 Closed ngonthier opened this issue on Jun 16, 2024 · 4 comments ngonthier commented on Jun 16, 2024 • edited **Have I written custom code **: TestFFT2D.py OS Platform and Distribution: Linux Ubuntu 16.04 TensorFlow installed … WebESP32-S2 has a DMA engine which can help to offload internal memory copy operations from the CPU in a asynchronous way. The async memcpy API wraps all DMA configurations and operations, the signature of esp_async_memcpy () is almost the same to the standard libc one. Thanks to the benefit of the DMA, we don’t have to wait for each …

WebAug 14, 2024 · When I tried to run the new project, I found memcpy() causing an UsageFault, caused by 32bit-wide Load/Store accessing an uneven address. I then … WebPrevent this fatal condition by deploying memcpy_mcsafe() in the fsdax read path. The main differences between this copy_to_user_mcsafe() and copy_user_generic_unrolled() are: * Typical tail/residue handling after a fault retries the copy byte-by-byte until the fault happens again.

WebMay 2, 2015 · memcpy doesn't work over a file descriptor, you can store the content of file1 in an array of chars (using fgets or fread) and then copy to file2 (using fputs or fwrite) …

Webstrcpy (and other str* methods) stop when they encounter a NULL (0) byte. memcpy and related functions to NOT stop when they encounter a NULL byte. If you have binary data, you must use memcpy. In your example, you are copying binary data, not string data. how much rain does the savanna getWebMar 19, 2014 · The error seems to occur randomly and I can't tie it to a task, parent or any other components of struct task_struct. I've tried mutexes and spinlocks to protect the … how much rain does the mojave desert getWebMay 24, 2010 · where as memcpy copies data (not character) from source to destination of given size n, irrespective of data in source. memcpy should be used if you know well … how much rain expected todayWebMay 2, 2015 · memcpy doesn't work over a file descriptor, you can store the content of file1 in an array of chars (using fgets or fread) and then copy to file2 (using fputs or fwrite) Also note that you need to use fclose () instead of close () with fopen () Share Improve this answer Follow edited May 2, 2015 at 11:18 answered May 2, 2015 at 10:58 David Ranieri how do people make alternate mapsWebJul 2, 2012 · Error Code: 3. CUDA Error Code: invalid argument. Cannot copy data from CPU to GPU. I wrote a test program (as shown below, and cudaMemcpy returned … how much rain does the taiga getWebApr 11, 2024 · The cited code: static MY_STRUCT mystruct; void Test() { memset(&mystruct, 0, sizeof(MY_STRUCT)); } Is a violation of MISRA C:2012 Required Rule 17.7 which states, unambiguously, that The value returned by a function having non-void return type shall be used.. memset() returns a void* and therefore to comply with … how do people make a babyWebOct 27, 2016 · So my understanding currently is that, if we are sure about the pointer we are passing, memcpy() can always be used in place of copy_to_user. Please correct me if … how do people lose weight fast