Write a function of the same dup2 function, cannot call the FCNTL function, and must have error handling __ function

Use the original DUP function of the system when implemented

MYDUP2.C//2015/08/17 Lucifer Zhang version1.0//write my own dup2 function//use DUP () function when inplemen tation #include <unistd.h>//include DUP () #include <stdio.h> #include <stdlib.h> #define OPEN_MAX 25 

6/* When the descriptor is negative or greater than Open_max, 'll make a errro * */int my_dup2 (int fd, int newfd);
    
    int main (int argc, char *argv[]) {int NEWFD, RETURN_FD;
        if (argc!= 2) {printf ("usage:a.out test.txt\n");
    Exit (0);
    printf ("Please input the descriptor than your want to set:");

    scanf ("%d", &AMP;NEWFD);
    Open a file int fd = open (Argv[1], 0);
    if (fd = = 1) {perror (argv[1]);//Print error MSG exit (0);
    printf ("Old descriptor is:%d\n", FD);
    RETURN_FD = My_dup2 (fd, NEWFD);
    printf ("New descriptor is:%d\n");
    Close (FD);

    Close (RETURN_FD);
Exit (0);
    int my_dup2 (int fd, int newfd) {int count = 0; int FDARRY[NEWFD]; 
        Record opened descriptor if (NEWFD < 0 | | | NEWFD > Open_max) {printf ("The New descriptor error!\n");
    Exit (0); }//DUP () return the lowest-numbered available file descriptor if ((Fdarry[count] = DUP (FD)) = = 1) {PR
        Intf ("DUP () function error!\n");
    Exit (0);
    else {//test old file descriptor if can is used close (Fdarry[count]);
    }//If FD equals NEWFD, then Dup2 returns NEWFD without it if (fd = = closing) {return FD; Close (NEWFD); Close//The main implementation for (count = 0; count <= newfd ++count) {if ((fdarry[count) = du
            P (FD) = = = 1) {printf ("dup () Funciont error!\n");
        Exit (0);
            else {printf ("The descriptor is:%d\n", Fdarry[count]);
            if (fdarry[count] = = NEWFD) {break; for (count = 0; count <= newfd; ++count) {if (Fdarry[coUNT] = = NEWFD) {return fdarry[count];
        else {close (Fdarry[count]);
 }
    }
}