#!/bin/ksh
# 
# ver 1.0, mwang@mindspring.com, January 1998
# * First internet "release" with basic functionality.
# ver 2.0, mwang@mindspring.com, August 1998
# * Added recursive put/get. 
# ver 2.1, mwang@mindspring.com, January 1999
# * Fixed the bug in trap statement pointed out by lars.g.lindberg@seab.se
#   and vincent.bienfait@seab.se and with their suggestions. 
# * Fixed a problem with -i option with /absolute/path. 
# * changed j=${i#./#/} to l=${i#./}, j=${l#/} for compatibility.
# * tighten up the code.
# ver 2.11, mwang@mindspring.com, March 2000
# * Fixed a typo: ${0%niftpget}niftp -t => ${0%niftpput}niftp -t
# ver 2.12, mwang@mindspring.com, June 2001
# * Added -k (ftp_command) to send arbitrary ftp command, eg quote site ...
# * Added checking for mainframe FTP server message:
#   "250 Transfer completed successfully"
#   "normal" FTP server has the message:
#   "226 .*Transfer complete."
 
OPATH=$PATH
PATH=$(PATH=/usr/bin:/bin:/usr/sbin:/sbin getconf PATH)

(( $# == 0 )) || [[ $1 = "help=y" ]] && {
  (typeset -x PATH=$OPATH; whence perl >/dev/null) || {
    print -r -- "It requires perl in your PATH to view the man page."
    exit 1
  }
  ME=$(basename $0)
  typeset TEMPDIR
  until [[ -n $TEMPDIR ]] && mkdir -p $TEMPDIR; do
    TEMPDIR=/tmp/$ME.$$.$RANDOM
  done
  trap "rm -rf $TEMPDIR" EXIT INT
  sed -n "/^## /s:^## ::p" $0 > $TEMPDIR/$ME.pod
  (typeset -x PATH=$OPATH; perldoc $TEMPDIR/$ME.pod)
  exit 100
}

[[ $0 = *"niftpget" ]] && exec ${0%niftpget}niftp -g "$@"
[[ $0 = *"niftpput" ]] && exec ${0%niftpput}niftp -t "$@"

while getopts :hf:gtbas:u:p:d:r:c:n:yw:l:o:q:x:i:z:j:v:ek: c
do
  case $c in
    f) f_opt=1; f_arg=$OPTARG;;
    g) g_opt=1;;
    t) t_opt=1;;
    b) b_opt=1;;
    a) a_opt=1;;
    s) s_opt=1; s_arg=$OPTARG;;
    u) u_opt=1; u_arg=$OPTARG;;
    p) p_opt=1; p_arg=$OPTARG;;
    d) d_opt=1; d_arg=$OPTARG;;
    r) r_opt=1; r_arg=$OPTARG;;
    c) c_opt=1; c_arg=$OPTARG;;
    n) n_opt=1; n_arg=$OPTARG;;
    y) y_opt=1;;
    w) w_opt=1; w_arg=$OPTARG;;
    l) l_opt=1; l_arg=$OPTARG;;
    o) o_opt=1; o_arg=$OPTARG;;
    q) q_opt=1; q_arg=$OPTARG;;
    x) x_opt=1; x_arg=$OPTARG;;
    i) i_opt=1; i_arg=$OPTARG;;
    z) z_opt=1; z_arg=$OPTARG;;
    j) j_opt=1; j_arg=$OPTARG;;
    v) v_opt=1; v_arg=$OPTARG;;
    e) e_opt=1;;
    k) k_opt=1; k_arg=$OPTARG;;
    ?) exec $0;;
  esac
done

shift $(($OPTIND - 1))
_ARG="$@"

RUN_USER=$(id -un)
[[ -f ~$RUN_USER/.niftp ]] && FTPCFG=~$RUN_USER/.niftp
[[ $f_opt = 1 ]] && FTPCFG=$f_arg
[[ -n "$FTPCFG" && -r "$FTPCFG" ]] && . $FTPCFG

(( m = 0 ))
[[ $k_opt = 1 || -n "$FTP_COMMAND"    ]] && (( m += 64 ))  # 1000000
[[ $g_opt = 1 || $GET_OR_PUT = "mget" ]] && (( m += 32 ))  # 0100000
[[ $t_opt = 1 || $GET_OR_PUT = "mput" ]] && (( m += 16 ))  # 0010000
[[ $x_opt = 1 || -n "$FTP_GET_FILES"  || 
   $i_opt = 1 || -n "$FTP_GETR_DIRS"  ]] && (( m += 08 ))  # 0001000
[[ $z_opt = 1 || -n "$FTP_PUT_FILES"  ]] && (( m += 04 ))  # 0000100
[[ $j_opt = 1 || -n "$FTP_JUNK_FILES" ]] && (( m += 02 ))  # 0000010
[[ $v_opt = 1 || -n "$FTP_VIEW_FILES" ]] && (( m += 01 ))  # 0000001

(( (m&48) == 48 )) && { print -r -- "-g and -t    cannot both set."; exit 102; }
(( (m&40) == 40 )) && { print -r -- "-g and -x/-i cannot both set."; exit 102; }
(( (m&36) == 36 )) && { print -r -- "-g and -z    cannot both set."; exit 102; }
(( (m&24) == 24 )) && { print -r -- "-t and -x/-i cannot both set."; exit 102; }
(( (m&20) == 20 )) && { print -r -- "-t and -z    cannot both set."; exit 102; }

(( m == 0 )) && {
  print -r -- "There is nothing to do."
  exit 103
}

[[ $g_opt = 1 ]] && GET_OR_PUT=mget
[[ $t_opt = 1 ]] && GET_OR_PUT=mput

[[ $b_opt = 1 && $a_opt = 1 ]] && {
  print -r -- "-b and -a cannot both set."
  exit 104
}
 
[[ $b_opt = 1 ]] && BIN_OR_ASC=binary
[[ $a_opt = 1 ]] && BIN_OR_ASC=ascii

[[ $s_opt = 1 ]] && FTP_SERVER=$s_arg
[[ -z $FTP_SERVER ]] && {
  print -r -- "you must specify ftp_server option."
  exit 105
}

[[ $u_opt = 1 ]] && FTP_USER=$u_arg
: ${FTP_USER:=ftp}

[[ $p_opt = 1 ]] && FTP_PASSWD=$p_arg
[[ -z $FTP_PASSWD ]] && {
  if [[ $FTP_USER = "ftp" ]]; then
    FTP_PASSWD="-"
  else
    print -r -- "you must specify ftp server passwd."
    exit 106
  fi
}

[[ $d_opt = 1 ]] && TARGET_DIR=$d_arg
[[ $r_opt = 1 ]] && SOURCE_DIR=$r_arg

[[ -n "$_ARG" ]] && {
  if [[ "$_ARG" = ftp://*([! ]) ]]; then
    FTP_URL="$_ARG"
    i=${FTP_URL#ftp://}
    FTP_SERVER=${i%%/*}
    j=${i#*/}
    TARGET_DIR=${j%/*}
    [[ $TARGET_DIR = $j ]] && TARGET_DIR=
    FTP_FILES=${j##*/}
  else
    FTP_FILES="$_ARG"
    [[ "$FTP_FILES" = "-" ]] && {
      [[ -z "$FTP_INPUTS" ]] && {
        FTP_INPUTS=$(cat)
      }
      FTP_FILES="$FTP_INPUTS"
    }
  fi
}

[[ -n "$GET_OR_PUT" && -z "$FTP_FILES" ]] && {
    print -r -- "you must specify files to get or to put."
    exit 107
}

[[ $x_opt = 1 ]] && FTP_GET_FILES=$x_arg
[[ "$FTP_GET_FILES" = "-" ]] && { 
  [[ -z "$FTP_INPUTS" ]] && {
    FTP_INPUTS=$(cat)
  }
  FTP_GET_FILES="$FTP_INPUTS"
}

[[ $i_opt = 1 ]] && FTP_GETR_DIRS=$i_arg
[[ "$FTP_GETR_DIRS" = "-" ]] && { 
  [[ -z "$FTP_INPUTS" ]] && {
    FTP_INPUTS=$(cat)
  }
  FTP_GETR_DIRS="$FTP_INPUTS"
}

[[ $z_opt = 1 ]] && FTP_PUT_FILES=$z_arg
[[ "$FTP_PUT_FILES" = "-" ]] && { 
  [[ -z "$FTP_INPUTS" ]] && {
    FTP_INPUTS=$(cat)
  }
  FTP_PUT_FILES="$FTP_INPUTS"
}

[[ $v_opt = 1 ]] && FTP_VIEW_FILES=$v_arg
[[ "$FTP_VIEW_FILES" = "-" ]] && { 
  [[ -z "$FTP_INPUTS" ]] && {
    FTP_INPUTS=$(cat)
  }
  FTP_VIEW_FILES="$FTP_INPUTS"
}

[[ $j_opt = 1 ]] && FTP_JUNK_FILES=$j_arg
[[ "$FTP_JUNK_FILES" = "-" ]] && { 
  [[ -z "$FTP_INPUTS" ]] && {
    FTP_INPUTS=$(cat)
  }
  FTP_JUNK_FILES="$FTP_INPUTS"
}

[[ $k_opt = 1 ]] && FTP_COMMAND=$k_arg
[[ "$FTP_COMMAND" = "-" ]] && {
  [[ -z "$FTP_INPUTS" ]] && {
    FTP_INPUTS=$(cat)
  }
  FTP_COMMAND="$FTP_INPUTS"
}

[[ $w_opt = 1 ]] && FIREWALL_SERVER=$w_arg
[[ $l_opt = 1 ]] && FIREWALL_USER=$l_arg
[[ $o_opt = 1 ]] && FIREWALL_PASSWD=$o_arg
[[ $q_opt = 1 ]] && FIREWALL_ACCOUNT=$q_arg
[[ $y_opt = 1 ]] && FIREWALL_ACCESS="yes"

[[ $c_opt = 1 ]] && FTP_CNT_MAX=$c_arg
: ${FTP_CNT_MAX:=5}

[[ $n_opt = 1 ]] && FTP_SECOND=$n_arg
: ${FTP_SECOND:=3600}

if [[ $FIREWALL_ACCESS = "yes" ]]; then
  [[ -z $FIREWALL_SERVER ]] && {
    print -r -- "you must specify firewall server."; exit 108; }
  [[ -z $FIREWALL_USER ]] && {
    print -r -- "you must specify firewall login."; exit 109; }
  [[ -z $FIREWALL_SERVER ]] && {
    print -r -- "you must specify firewall passwd."; exit 110; }
  SERVER=$FIREWALL_SERVER
  FTP_COMMANDS=$(
    print -r -- "user $FIREWALL_USER $FIREWALL_PASSWD $FIREWALL_ACCOUNT"
    print -r -- "quote site $FTP_SERVER")
else
  SERVER=$FTP_SERVER
  FTP_COMMANDS=
fi

FTP_COMMANDS=$([[ -n "$$FTP_COMMANDS" ]] && print -r -- "$FTP_COMMANDS" 
               print -r -- "user $FTP_USER $FTP_PASSWD"
               [[ -n "$TARGET_DIR" ]] && print -r -- "cd $TARGET_DIR"
               [[ -n "$SOURCE_DIR" ]] && print -r -- "lcd $SOURCE_DIR"
               [[ -n "$BIN_OR_ASC" ]] && print -r -- "$BIN_OR_ASC"
               print -r -- "prompt"
              ) 

tmpa=/tmp/.niftpa-$$
tmpb=/tmp/.niftpb-$$
trap "set +o noglob; rm -f ${tmpa}-[0-9]* ${tmpb}-[0-9]*; exit" 0 1 2 3

set -o noglob
rm -rf $tmpa-0
rm -rf $tmpa-1
rm -rf $tmpa-2

[[ -n "$FTP_COMMAND" ]] && print -- "$FTP_COMMAND" >> $tmpa-0
# "\n" in "delete file\ndir" ok.

for m in FTP_FILES FTP_GET_FILES FTP_PUT_FILES
do
  [[ $m = FTP_FILES ]] && mgp=$GET_OR_PUT
  [[ $m = FTP_GET_FILES ]] && mgp=mget
  [[ $m = FTP_PUT_FILES ]] && mgp=mput
  gp=${mgp#m}
  eval n="\$$m"
  [[ -z "$n" ]] && continue
  for i in $n
  do
    l="${i#./}"
    j="${l#/}"
    k=${j%/*}
    f=${j##*/}
    if [[ $j = $k ]]; then p=; else p=$k/; fi
    [[ -n "$f" ]] && {
      if [[ "$f" = *"*"* ]]; then
        print -r -- "$mgp $p$f" >> $tmpa-0
      else
        print -r -- "$gp $i $p$f" >> $tmpa-0
      fi
    }
    until [[ $j = $k ]]
    do
      [[ $mgp = "mget" ]] && print -r -- "!mkdir $k" >> $tmpa-1
      [[ $mgp = "mput" ]] && print -r -- "mkdir $k" >> $tmpa-1
      j=$k
      k=${j%/*}
    done
  done
done 
[[ -f $tmpa-1 ]] && sort -u -o $tmpa-1 $tmpa-1
[[ -f $tmpa-0 ]] && cat $tmpa-0 >> $tmpa-1
rm -f $tmpa-0

[[ -n "$FTP_JUNK_FILES" ]] && {
  for i in $FTP_JUNK_FILES
  do
    j="${i%/}"
    if [[ "$i" = "$j" ]]; then
      print -r -- "mdelete $j" >> $tmpa-1
    else
      print -r -- "rmdir $j" >> $tmpa-0
    fi
  done
  [[ -f $tmpa-0 ]] && sort -ur $tmpa-0 >> $tmpa-1
  rm -f $tmpa-0
}

[[ -n "$FTP_VIEW_FILES" ]] && {
  for i in $FTP_VIEW_FILES
  do
    if [[ "$i" = "." ]]; then
      print -r -- "ls -alR"
    else
      print -r -- "dir $i" >> $tmpa-1
    fi
  done
}

[[ $e_opt = 1 ]] && {
  print -r -- GET_OR_PUT: $GET_OR_PUT
  print -r -- BIN_OR_ASC: $BIN_OR_ASC
  print -r -- FTP_URL: $FTP_URL
  print -r -- FTP_SERVER: $FTP_SERVER
  print -r -- FTP_USER: $FTP_USER
  print -r -- FTP_PASSWD: $FTP_PASSWD
  print -r -- TARGET_DIR: $TARGET_DIR
  print -r -- FTP_FILES: $FTP_FILES
  print -r -- FTP_PUT_FILES: $FTP_PUT_FILES
  print -r -- FTP_GET_FILES: $FTP_GET_FILES
  print -r -- FTP_VIEW_FILES: $FTP_VIEW_FILES
  print -r -- FTP_JUNK_FILES: $FTP_JUNK_FILES
  print -r -- SOURCE_DIR: $SOURCE_DIR
  print -r -- FIREWALL_ACCESS: $FIREWALL_ACCESS
  print -r -- FIREWALL_SERVER: $FIREWALL_SERVER
  print -r -- FIREWALL_USER: $FIREWALL_USER
  print -r -- FIREWALL_PASSWD: $FIREWALL_PASSWD
  print -r -- FTP_CNT_MAX: $FTP_CNT_MAX
  print -r -- FTP_SECOND: $FTP_SECOND
  print -r -- SERVER: $SERVER
  print -r -- FTP_COMMANDS: 
  print -r -- "$FTP_COMMANDS"
  [[ -f $tmpa-1 ]] && cat $tmpa-1
  exit 150
}

(( FTP_CNT = 0 ))
(( NOK = 0 ))

while (( FTP_CNT < FTP_CNT_MAX ))
do
  (( FTP_CNT += 1 ))
  if [[ -f $tmpa-1 ]]; then
    cp $tmpa-1 $tmpa-0
  else
    > $tmpa-0
  fi
  { print -r -- "niftp starts (trial $FTP_CNT)."
    if [[ $FIREWALL_ACCESS = "yes" ]]; then
      print -r -- "connecting $FTP_SERVER (via firewall ${FIREWALL_SERVER})."
    else
      print -r -- "connecting $FTP_SERVER."
    fi
  } | tee -a $tmpa-2

  { print -r -- "$FTP_COMMANDS"
    cat $tmpa-0
    if [[ -n "$FTP_GETR_DIRS" ]]; then
      NP=0
      j=
      for i in $FTP_GETR_DIRS
      do
        (( NP += 1 ))
        rm -f $tmpb-$NP
        [[ -z "$j" ]] && print -r -- "pwd"
        if [[ -n "${SOURCE_DIR}" ]]; then
          mkdir -p "${SOURCE_DIR%/}/${i#./}"
        else
          mkdir -p "./${i#./}"
        fi
        if [[ "$i" = "." ]]; then
          k=
          l=
        else
          print -r -- "cd $i"
          k=${i%/}/
          l=${k#/}
        fi
        print -r -- "mls -aR $tmpb-$NP"
        print -r -- "!touch $tmpb-0"
        while [[ ! -f $tmpb-0 ]]
        do
          sleep 3
        done
        [[ -z "$j" ]] && {
          j=$(tail -10 $tmpa-2 |
              sed -n "s:^257 \"\(.*\)\" is current directory.*\$:\1:p")
        }
        print -r -- "cd $j"
        ${0%niftp}ls-aR2find -d - $tmpb-$NP |
          sed "/^\.$/d; s:^\./::; s:^:!mkdir $l:"
        ${0%niftp}ls-aR2find -f - $tmpb-$NP |
          sed "s:^\./::; s:^\(.*\)\$:get $k\1 $l\1:"
        rm -f $tmpb-$NP
        rm -f $tmpb-0
      done
    fi | tee -a $tmpa-0
    print -r -- "quit" 
  } | ftp -nv $SERVER 2>&1 | tee -a $tmpa-2

  print -r -- "niftp stops (trial $FTP_CNT)." | tee -a $tmpa-2
  NOK=$(sed -n "/^niftp starts (trial $FTP_CNT)/,\$p" $tmpa-2 |
        egrep -c "^226 .*Transfer complete|^250 Transfer completed successfully|^250 DELE command successful")
  if [[ -n "$FTP_GETR_DIRS" ]]; then
    set $FTP_GETR_DIRS; NP=$#
  else
    NP=0
  fi
  (( NOK -= NP ))  # each DIR has one extra dir counted, as shown below.
# 150 ASCII data connection for /bin/ls (127.0.0.1,56724) (0 bytes).
# 226 ASCII Transfer complete.
  NUM=$(egrep -c "^m?put|^m?get|^m?delete|^dir" $tmpa-0)
  print -r -- "Finished $NOK/$NUM operations (GET/PUT/DELE/DIR)."
  if (( NOK >= NUM || FTP_CNT_MAX == 1 )); then
    (( FTP_CNT = FTP_CNT_MAX ))
  else
    sleep $FTP_SECOND
  fi
done

if (( NOK >= NUM )); then
  exit 0
else
  exit 200
fi

## =head1 NAME
## 
## niftp, niftpget, niftpput: non-interactive recursive ftp ksh script.
## 
## =head1 SYNOPSIS
## 
## B<niftp> I<options> I<[files]>
## 
## B<niftpget> I<options> I<[files]>
## 
## B<niftpput> I<options> I<[files]>
## 
## =head1 DESCRIPTION
## 
## I<niftp> GET/PUT/DELETE/DIR files on ftp server non-interactively. It 
## supports firewall, recursive GET/PUT, standard input, list of pathnames,
## file glob (wildcard *). 
## 
## I<niftp> counts the number of operations requested and the number of 
## operations successfully finished. It returns 0 upon successful completion 
## and has an option for retrial in case of error. 
##      
## =head2 OPTIONS
## 
## The options can be provided either by command line or configuration 
## file. The command line options overwrite the configuration file, and 
## FTP_URL option overwrites other options. The configuration file options
## are listed after the command line options below. 
## 
## =item B<-f>
## 
## Specify the configuration file, default $HOME/.niftp.
## 
## =item B<help=y>
## 
## Display this man page.
## 
## =item B<-g, GET_OR_PUT=I<mget>>
##  
## To get files. You can also use -x option, -g option is kept for
## compatibility with earlier versions.
## 
## =item B<-t, GET_OR_PUT=I<mput>>
## 
## To put files. You can also use -z option, -t option is kept for
## compatibility with earlier versions. -g and -t can not be used
## together, but -x and -z can. 
## 
## =item B<-b, BIN_OR_ASC=I<binary>>
## 
## To get/put files under binary mode. This is the default.
## 
## =item B<-a, BIN_OR_ASC=I<ascii>>
## 
## To get/put files under ascii mode.
## 
## =item B<-s I<ftp_server>, FTP_SERVER=I<ftp_server>>
## 
## Specify the ftp server.
## 
## =item B<-u <ftp_user>, FTP_USER=I<ftp_user>>
## 
## Specify the ftp user. The default is I<ftp>.
## 
## =item B<-p I<ftp_passwd>, FTP_PASSWD=I<ftp_passwd>>
## 
## Specify the ftp password. The default is "-" if the ftp user is 
## "ftp".
## 
## =item B<-d I<target_dir>, TARGET_DIR=I<target_dir>>
## 
## Change the current directory to <target_dir> on the remote machine.
## 
## =item B<-r I<source_dir>, SOURCE_DIR=I<source_dir>>
## 
## Change the current directory to <source_dir> on the local machine.
## 
## =item B<-y, FIREWALL_ACCESS=I<yes|no>>
## 
## To access the ftp server via firewall if -y is used or 
## FIREWALL_ACCESS is set to "yes". Otherwise access the ftp server
## directly, which is the default. 
## 
## =item B<-w I<firewall_server>, FIREWALL_SERVER=I<firewall_server>>
## 
## Specify the firewall server. 
## 
## =item B<-l I<firewall_user>, FIREWALL_USER=I<firewall_user>>
## 
## Specify the firewall user. 
## 
## =item B<-o I<firewall_passwd>, FIREWALL_PASSWD=I<firewall_passwd>>
## 
## Specify the firewall password. 
## 
## =item B<-q I<firewall_account>, FIREWALL_ACCOUNT=I<firewall_account>>
## 
## Specify the firewall account number. Some firewalls requires this.
## 
## =item B<-n I<ftp_second>, FTP_SECOND=I<ftp_second>>
## 
## Specify the trial interval. niftp counts how many operations
## you requested (NUM), and how many operations finished successfully
## (NOK). If the NOK is less than NUM it is considered as a failure and
## will retry. The default is 3600 seconds, i.e. 1 hour. 
## 
## =item B<-c I<ftp_cnt_max>, FTP_CNT_MAX=I<ftp_cnt_max>>
## 
## Specify the number of trials. The default is 5. 
## 
## =item B<-x I<get_files|->, FTP_GET_FILES=I<get_files>>
## 
## =item B<-z I<put_files|->, FTP_PUT_FILES=I<put_files>>
## 
## =item B<-j I<junk_files|->, FTP_JUNK_FILES=I<junk_files>>
## 
## =item B<-v I<view_files|->, FTP_VIEW_FILES=I<view_files>>
## 
## Specify the files to GET/PUT/DELETE/DIR. If it is a dash "-", the
## files are from the standard input. Directory is denoted by the "/" 
## at the end of the pathname. When you use '*' in filename, specify
## working directory with -d or -r option and use relative pathname. 
## 
## =item B<I<files|->, FTP_FILES=I<files>>
## 
## Specify the files OR URL to GET(-g) or PUT(-t). Besides the URL
## option it is the same as -x and -z, and is kept for compatibility 
## with early versions. 
## 
## =item B<-i, FTP_GETR_DIRS=I<ftp_getr_dirs>>
## 
## GET files under <ftp_getr_dirs> recursively. 
## 
## =item B<-e>
## 
## Debug mode. To check various parameters only. It does not connect to
## the ftp server. 
## 
## =item B<-k, FTP_COMMAND=I<ftp_command|->>
## 
## Issue specified ftp commands.  If it is a dash "-", the commands are from
## the the standard input.
## 
## =head1 EXAMPLES
## 
##   $HOME/.niftp: 
##     FIREWALL_SERVER=<firewall_server>
##     FIREWALL_USER=<firewall_user>
##     FIREWALL_PASSWD=<firewall_passwd>
##     FTP_SERVER=<ftp_server>
##     FTP_USER=<ftp_user>
##     FTP_PASSWD=<ftp_passwd>
## 
## =item B<niftpget -y ftp://prep.ai.mit.edu/pub/gnu/ghost\*.tar.gz>
## 
## GET all files matching ghost*.tar.gz under the directory
## pub/gnu from the ftp server prep.ai.mit.edu via firewall. 
## 
## =item B<find unix-prog -type f | niftp -y -d ftp -z ->
## 
## Put all files under unix-prog (including unix-prog) to
## ftp server specified in $HOME/.niftp file with the same
## directory structure. 
## 
## =item B<niftp -s ftp.mindspring.com -u I<user> -p I<pass> -d ftp -v .>
## 
## Connecting ftp server ftp.mindspring.com with I<user> and I<pass>
## and view all files under current directory. 
## 
## =item B<niftp -s ftp.mindspring.com -u I<user> -p I<pass> -d ftp -j I<junk_files>>
## 
## Connecting ftp server ftp.mindspring.com with I<user> and I<pass>
## and delete I<junk_files>. 
## 
## =item B<niftp -y -s sunsite.unc.edu -i pub/multimedia/chinese-music>
## 
## Download all files recursively under pub/multimedia/chinese-music
## on sunsite.unc.edu via firewall. 
## 
## The options -x(get), -z(put), -v(listing), -j(delete) can be combined.
## 
## =head1 FILES
## 
##     niftp, niftpget, niftpput: these files should be hardlinked. 
##     ls-aR2find
## 
## =head1 SEE ALSO
## 
## L<ftp(1)>, L<wget(1)>, L<Net::FTP(3)>, I<ncftp(1)>
## 
## =head1 CAVEATS
## 
## Symbolic links to files are treated as seperate regular files. Symbolic
## links to directories are errored out. Recursive GET only works on servers 
## who understand "mls -aR". 
## 
## =head1 AUTHOR
## 
## This is free software. You may copy or redistribute it under the same
## terms as Perl itself.
##  
## If you modify it, please send a copy of your modification to me.
## 
## Copyright (C) Michael Wang, mwang@mindspring.com
## 1998-2001