debian man page for fd_copy

fd_copy(3)						     Library Functions Manual							fd_copy(3)

NAME
       fd_copy - duplicate a descriptor

SYNTAX
       #include <fd.h>

       int fd_copy(to,from);

       int to;
       int from;

DESCRIPTION
       fd_copy	copies descriptor from to descriptor to.  If to was already open, fd_copy closes it.  fd_copy always leaves from intact; if to and
       from are the same number, fd_copy does nothing.

       fd_copy returns 0 on success, -1 on error.  fd_copy does not guarantee that to will remain open, if it was open, in case of error.

SEE ALSO
       dup(2), fd_move(3)

																	fd_copy(3)