Question

I wrote a script to download some data from FTP by a subroutine. I tell the program to download the data that belong to my stations which are listed in @station_list array with capital letters. The corresponding data are located at separate pages with the name of the each station in small letters, e.g. ftp://$ftp_srv/$ftp_dir/aaaa is the page for aaaa station and ftp://$ftp_srv/$ftp_dir/bbbb is the page for bbbb station. So, I make a loop for downloading and converting the capital letters to small ones. But it just work for the first station. I don’t know what shall I do to fix it. Thank you for any help.
The following code is the mentioned loop:

foreach $station (@station_list) {

    $litte_station = "\L$station\E";

    unless ($ftp->cwd($litte_station)) {
        $ftp->quit;
        print2("Can't cd to $station  $!\n");
        return (0);
    }

    $filename = "\L${station}\E${doy}\L$sessionchar\E.${yy}o.gz";
    print2 ("Get file: ${ftp_srv}\\${ftp_dir}\\${yyyy}\\${doy}\\${filename} ...");

    unless ($ftp->get($filename, $ftp_savepath.$filename)) {
        print2(" NOT AVAILABLE\n");
    } else {
        print2 (" Successful \n");   
    }
}

Answer 1

In response to your comment on my first answer, I now better understand what you were asking. At the end of your foreach loop, call $ftp->cdup:

foreach my $station (@station_list) {
    $ftp->cwd(lc $station);
    # ...
    $ftp->cdup;
}

That will return you to the parent directory.