C++ Linux TCP sockets fd

Question

how do i change the socket id/FD after i use accept() ? lets say i bind() on sockfd 3 and the accepted client is on sockfd 4, how do i change/move that sockfd to 1000?

OS : Ubuntu

Answer 1

Still you didn't specify the OS so I will go with *nix :)

http://linux.die.net/man/2/dup2