tail.cpp

This must be done in C++.

./tail [-n number] [file]

The tail utility shall copy its input file to the standard output beginning at a designated place. Copying shall begin at the point in the file indicated by the -n number option. The option-argument number shall be counted in units of lines. Line counts start from 1. Tails relative to the end of the file may be saved in an internal buffer, and thus may be limited in length. Such a buffer, if any, shall be no smaller than 2048*10 bytes. If no file operand is specified, or when file is -, then standard input is assumed.

-n number: This option shall be equivalent to -c number, except the starting location in the file shall be measured in lines instead of bytes. If neither -c nor -n is specified, -n 10 shall be assumed.