How to copy text file in C or C++?

Question

When trying to copy a text file A to another file B, there may have several methods: 1) byte by byte 2) word by word 3) line by line

which one is more efficient?

Answer 1

Just "buffer by buffer", copy files in binary mode and read/write X bytes long parts. I think that fastest solution is to just use copy function of C language itself or system call.

Largest buffer will provide you less HDD find for data operations (faster copying) but more RAM usage.