A Python interface to sendfile(2) syscall
sendfile(2) is a system call which provides a "zero-copy" way of copying data from one file descriptor to another (a socket). The phrase "zero-copy" refers to the fact that all of the copying of data between the two descriptors is done entirely by the kernel, with no copying of data into userspace buffers. This is particularly useful when sending a file over a socket (e.g. FTP).