c++ - How to get a pointer to the beginning of a file in C++

Question

Is it possible in C++ to somehow get a pointer to the beginning of an opened file so that it ( the pointer ) can be passed to the unix write function together with the size of the file?

Just to be clear: I want to pass the whole file to a write-like function - how do I do this?

Answer 1

你可以只mmap()写完整的文件，然后把这个指针传给write。您必须使用open(), 来打开它，但不是fopen()。

Answer 2

sendfile() is specifically for this purpose on POSIX platforms when sending over the network, and the kernel handles the intricacies of doing it.