memsetbuf
Memsetbuf is a function in the C programming language used to fill a block of memory with a specified value. It is part of the standard library and is declared in the string.h header file. The function prototype is void *memsetbuf(void *s, int c, size_t n, size_t bufsize). Unlike the standard memset function, memsetbuf takes an additional parameter, bufsize, which specifies the size of the buffer to be filled. This function is particularly useful when working with fixed-size buffers, as it ensures that the buffer is not overfilled. The function returns a pointer to the memory area s. If the buffer size is less than the number of bytes to be filled, the function will only fill up to the buffer size. This can help prevent buffer overflow vulnerabilities, which are a common security risk in software development.