Read memory and store to a 16KB buffer, then output to a file. Pseudo code.

read_mem_to_buffer.cpp

const size_t buffSize = 16 * 1024; // 16KB
size_t currReadSize = buffSize; // default
size_t dumpedSize = 0;
uint8 currBuff[buffSize];
while (currAddr < endAddr) 
{
    currReadSize = (currAddr + buffSize <= endAddr) ? buffSize : (size_t)(endAddr - currAddr); 
		read_memory(currBuff, currAddr, sizeof(uint8) * currReadSize, memory_type);
		dumpedSize += currReadSize;
		currAddr += currReadSize;
}
	
for (size_t i = 0; i < dumpedSize; ++i)
{
    fprintf(memory_output_file,"%02x\n", currBuff[i]);
}