#!/usr/bin/env perl
# +-======-+ 
#  Copyright (c) 2003-2007 United States Government as represented by 
#  the Admistrator of the National Aeronautics and Space Administration.  
#  All Rights Reserved.
#  
#  THIS OPEN  SOURCE  AGREEMENT  ("AGREEMENT") DEFINES  THE  RIGHTS  OF USE,
#  REPRODUCTION,  DISTRIBUTION,  MODIFICATION AND REDISTRIBUTION OF CERTAIN 
#  COMPUTER SOFTWARE ORIGINALLY RELEASED BY THE UNITED STATES GOVERNMENT AS 
#  REPRESENTED BY THE GOVERNMENT AGENCY LISTED BELOW ("GOVERNMENT AGENCY").  
#  THE UNITED STATES GOVERNMENT, AS REPRESENTED BY GOVERNMENT AGENCY, IS AN 
#  INTENDED  THIRD-PARTY  BENEFICIARY  OF  ALL  SUBSEQUENT DISTRIBUTIONS OR 
#  REDISTRIBUTIONS  OF THE  SUBJECT  SOFTWARE.  ANYONE WHO USES, REPRODUCES, 
#  DISTRIBUTES, MODIFIES  OR REDISTRIBUTES THE SUBJECT SOFTWARE, AS DEFINED 
#  HEREIN, OR ANY PART THEREOF,  IS,  BY THAT ACTION, ACCEPTING IN FULL THE 
#  RESPONSIBILITIES AND OBLIGATIONS CONTAINED IN THIS AGREEMENT.
#  
#  Government Agency: National Aeronautics and Space Administration
#  Government Agency Original Software Designation: GSC-15354-1
#  Government Agency Original Software Title:  GEOS-5 GCM Modeling Software
#  User Registration Requested.  Please Visit http://opensource.gsfc.nasa.gov
#  Government Agency Point of Contact for Original Software:  
#  			Dale Hithon, SRA Assistant, (301) 286-2691
#  
# +-======-+ 
# ./acquire_obsys 19990721 180000 060000 6 sonde_hirs
# Script to make the acquire resource file and then call acquire script to get
#  observation data.
# See usage() of this script for more information.
#
# !REVISION HISTORY:
#
# 2001.07.31 Eueng-nan Yeh   Specs and man page.
# 2001.08.06 Eueng-nan Yeh   Initial code.
# 2001.10.02 Eueng-nan Yeh   obsys.rc format changed
# 2001.10.17 Eueng-nan Yeh   Accept multiple obclasses
# 2002.03.18 Eueng-nan Yeh   Added standard name output
# 2002.08.12 Tommy Owens     Returned with Warning if no records found for a given class
# 2002.08.14 Eueng-nan Yeh   Set the standard name after the old name
#                            Removed look ahead calculation from subroutine mk_date 
# 2004.10.21 Todling         Work around /bin/time command
#=========================================================================
      use warnings;
      use Getopt::Long;             # command line options

      @options = qw(cp d=s e=s f h lfn la=s p s=s ssh strict v drc=s acqfile=s);
      $ENV{PATH} = "./:" . $ENV{PATH};
      $tname = "obsys.rc";          # default dataBase table resource file
      $acqout = "obsys.acq";        # default acq file
      $exe_acquire = "acquire";     # file acquire
#      if(!(-e $exe_acquire)) {msg("E", "File '$exe_acquire' not found.");}

# Initialization
# --------------
      ($bymd,$bhms,$ihms,$nstep,$oclass,@opt_acq)=init($tname, @options);

# Generate YYYYMMDD array @ymd1
# -----------------------------
      @ymd1 = mk_date($bymd,$bhms,$ihms,$nstep,$opt_la);
      print("ymd1=@ymd1\n") if($opt_v);

# Define $acqfile as acqfilepath+obsys.acq or from input
# ----------------------------------------------------------
      ($opt_d = $opt_d) or ($opt_d = "./");   #destination path
      if( !(-e $opt_d) ) {                    #output dir not exist
        $status = system("mkdir -p $opt_d");
        if($status!= 0) {
          msg("E", "Fail to make output $opt_d");
        } else { msg("P", "Creating output path $opt_d");}
      }
      $acqpath = $opt_d;         #set $acqpath as $opt_d
      @class = split(/,/, $oclass);
      if($acqpath =~ /\/$/) {$acqfile = $acqpath . $acqout;
      } else { $acqfile = $acqpath . "/" . $acqout; }
      if($opt_acqfile) {          #user defined output acqfile full name
        $acqfile = $opt_acqfile;
        $i = rindex($acqfile, "/");
        if($i >= 0) {
          $i = substr($acqfile, 0, $i);
          if( !(-e $i) ) {                    #output dir not exist
            $status = system("mkdir -p $i");
            if($status!= 0) {
              msg("E", "Fail to make output $i");
            } else { msg("P", "Creating output path $i");}
          }
        }
      }
      print("acqfile = $acqfile\n") if($opt_v);

# Complete the acquire resource file $acqfile
# -------------------------------------------
      print(">> Creating acquire resource file $acqfile...\n") if($opt_v);
      open(LUNO,">$acqfile") || die "Fail to open files:$acqfile $!\n";
      for($i=0; $i<scalar(@class); $i++) {
        mk_rc($i, $opt_drc, $acqfile, $class[$i], @ymd1);
      }
      close(LUNO)|| die "Couldn't close file:$acqfile $!\n";
      print("Acquire file '$acqfile' completed.\n") if($opt_v);
      push(@opt_acq, "-rc $acqfile");
      push(@opt_acq, ($bymd,$bhms,$ihms,$nstep));

# Processing acquire
# ------------------
      if ( -e "/bin/time" ) {
      $com = "/bin/time $exe_acquire " . join(" ", @opt_acq);
      } else {
      $com = "$exe_acquire " . join(" ", @opt_acq);
      }
      print("com = $com\n") if($opt_v);
      print(">> Processing acquire...\n") if($opt_v);
      $status = system($com);
      if($status != 0) {  # error
        msg("E", "$com failed."); 
      } 

# All done
# --------
      print("Job finished.\n") if($opt_v);
      exit(0);   #0 as a success exit

#=========================================================================
#
# init: sets optional and required command line arguments
#
      sub init {
        my ($tname, @opt) = @_;
        my ($op1,$op2,$x,$rc,$bymd,$bhms,$ihms,$nste,$oclass,@opt_acq);
        my ($i, $j, $k, $n, @mday, $y4, $m2, $d2);

        @mday=(31,28,31,30,31,30,31,31,30,31,30,31);
        $rc = GetOptions(@opt);
        ($opt_h = $opt_h) or ($opt_h = 0);
        ($opt_la = $opt_la) or ($opt_la = 0);
        ($opt_drc = $opt_drc) or ($opt_drc = $tname);  
        if(!(-e $opt_drc)) {msg("E", "DataBase resource file '$opt_drc' not found.");}       
        print("Database resource file = $opt_drc\n") if ($opt_v);
        usage() if ($opt_h || !$rc || ($#ARGV != 4));
        ($bymd, $bhms, $ihms, $nstep, $oclass) =
          ($ARGV[0], $ARGV[1], $ARGV[2], $ARGV[3], $ARGV[4]);
        if(length($bymd) != 8) {msg("E","Beginning YYYYMMDD '$bymd' wrong");}
        $y4=substr($bymd,0,4);  $m2=substr($bymd,4,2);  $d2=substr($bymd,6,2);
        if($m2>12 || $m2<1) {msg("E","Beginning YYYYMMDD '$bymd' wrong");}
        if(($y4%4 == 0 && $y4%100 != 0) || $y4%400==0 ) {$mday[1] = 29;}
        if($d2>$mday[$m2-1] || $d2<1) {msg("E","Beginning YYYYMMDD '$bymd' wrong");}

        if(length($bhms) != 6 || $bhms >= 240000) {
          msg("E","Beginning HHMMSS '$bhms' wrong");
        }
   #     if(length($ihms) != 6 || $ihms>240000 || $ihms <=0) {
        if(length($ihms) != 6 || $ihms <=0) {
          msg("E","time step increment HHMMSS '$ihms' wrong");
        }
        if($nstep <= 0) {msg("E","Number of timesteps '$nstep' wrong");}

#Creating optional list for acquire script to use
        $n = scalar(@opt) - 2;    #do not include the last two options drc, acqfile
        $j = 0;
        for($i=0; $i<$n; $i++) {
          $k=index($opt[$i], "=");
          if($k >= 0) {    #with value
            $op1 = substr($opt[$i], 0, $k);
          } else { $op1 = $opt[$i]; }
          $op2 = '$'.opt_ . $op1;
          if( eval($op2) ) {     #option defined
            $value = "";
            if($k >= 0) {  #with value
              $value = " " . eval($op2);
            }
            $opt_acq[$j] = "-" . $op1 . $value;
            $j++
          }
        }   #End of for($i=0; $i<$n; $i++)
        return($bymd, $bhms, $ihms, $nstep, $oclass, @opt_acq);
      }

#=========================================================================
#
# mk_date: Returns with array of unique records of YYYYMMDD.
#
      sub mk_date {
        my($bymd,$bhms,$ihms,$nstep,$opt_la) = @_;
        my(@mday,@ymd,@ymd1,$y4,$m2,$d2,$i,$n,$m);
        @mday=(31,28,31,30,31,30,31,31,30,31,30,31);
        $m = 0;    $ymd[$m]=$bymd;
        $y4=substr($ymd[$m],0,4);  $m2=substr($ymd[$m],4,2);  $d2=substr($ymd[$m],6,2);
        if(($y4%4 == 0 && $y4%100 != 0) || $y4%400==0 ) { $mday[1] = 29; }
        $i = $nstep;
   ##     if($opt_la) { $i += $opt_la; }  #look ahead option
        for($n=1; $n<$i; $n++) {
          $bhms += $ihms;
          $m++;
#          if($n == $nstep) {  #if opt_la defined
#            $m = 0;
#            @ymd=();
#          }
          while($bhms >= 240000 ) {
            $bhms -= 240000;
            $d2++;
            if($d2>$mday[$m2-1]) {$d2 -= $mday[$m2-1];  $m2++;}
            if($m2>12) {
              $m2 -= 12;
              $y4++;
              if(($y4%4 == 0 && $y4%100 != 0) || $y4%400==0 ) {$mday[1] = 29; }
              else { $mday[1] = 28; }
            }
          }  #End of while($bhms >= 240000 )
          $ymd[$m]=$y4 . sprintf("%02d",$m2) . sprintf("%02d",$d2);
        } #End of for($n=1; $n<$i; $n++)
# make ymd unique.
        $m = 0;
        $ymd1[$m] = $ymd[0];
        for($i=1; $i<scalar(@ymd); $i++) {
          if($ymd[$i] > $ymd1[$m]) {
            push(@ymd1, $ymd[$i]);
            $m++;
          }
        }
        return(@ymd1);
      }

#=========================================================================
#
# mk_rc: make resource acquired file $acqfile
#
      sub mk_rc {
        my($nclass, $tname, $acqfile, $oclass, @ymd1) = @_;
        my($dtime, $n, $i, @tokens, $user, $standard);
        $n = 0;
# Check out valid records from the template file $tname for given class
#   $oclass and date $ymd1
        ($standard,@data) = ck_table($tname, $oclass, @ymd1);
      if ( scalar(@data) ){
            for($i=0; $i<scalar(@data); $i++) {
                if(length($data[$i]) > 10) {
                    $n = 1;
                    last;
                }
            }
        if($n == 0 ) { msg("W", "No valid records found on $tname."); }
   
        if($opt_v) {
           print("Acquired records:\n");
           for($i=0; $i<scalar(@data); $i++) { print("$data[$i]\n"); }
        }
        if($nclass == 0 ) {
          $user = $ENV{"USER"};
          $user = getlogin() unless $user;
          $dtime = `date '+%a %d %b %Y %H:%M:%S %p %Z'`;   chomp($dtime);
          print(LUNO "#\n");
          print(LUNO "# Acquiring rules                 $dtime\n");
          print(LUNO "# Created by $user\n") if $user;
          print(LUNO "#");  for($i=0; $i<64; $i++) {print(LUNO ".");}
          print(LUNO "\n");
        }
        $n = length($oclass)+7;
        print(LUNO "#\n");
        print(LUNO "#      "); for($i=0;$i<$n;$i++) {print(LUNO "-");}  print(LUNO "\n");
        print(LUNO "#       "); print(LUNO "$oclass Data\n");
        print(LUNO "#      "); for($i=0;$i<$n;$i++) {print(LUNO "-");}
 #       print(LUNO "\n# => $standard\n");
        print(LUNO "\n");
        for($i=0; $i<scalar(@data); $i++) { print(LUNO "$data[$i] => $standard\n"); }
      }else{
         msg("W", "No valid records found for $oclass."); 
      }
    }
#=========================================================================
#
# ck_table: get valid records @data1 from database template file $tname
#
      sub ck_table {
        my($tname, $oclass, @ymd1) = @_;
        my($i, @arr,$data1, $nrcd, @field, @data, $m, @data1, @ar1);
        $m = scalar(@ymd1);
        $nrcd = 0;
        $cdate = `date '+%Y%m%d'`;  chomp($cdate);  #current date YYYYMMDD
        $warned = 0;
        open(LUN,"$tname") || die "Fail to open file: $tname $!\n";
LOOP1:  while( defined($rcd = <LUN>) ) {
          chomp($rcd);
          $rcd =~ tr/\t/ /s;   $rcd =~ tr/  / /s;   $rcd =~ s/^ | $//g;
          @arr = split(/ /, $rcd);
          if(length($rcd) <= 2  || $rcd =~ /#/ || scalar(@arr)<2) { next; };
          if($rcd =~ /^BEGIN/i && ($arr[1] eq $oclass)) { #found
            @ar1 = split(/=>/, $rcd);
            $standard = ".";
            if(scalar(@ar1) == 2) {$standard = $ar1[1]; }
            $standard =~ s/ //g;
            while( defined($rcd = <LUN>) ) {
              chomp($rcd);
              $rcd =~ tr/\t/ /s;   $rcd =~ tr/  / /s;   $rcd =~ s/^ | $//g;
              if(length($rcd) <= 2  || ($rcd =~ /#/)) { next; };
              if($rcd =~ /END/i) {  #end of block
                if ($nrcd <= 0) {   #no records
#TOWENS 8/5/2002  msg("E", "No valid record found for class '$oclass' from $ymd1[0] to $ymd1[$m-1] on $tname.");
                  msg("W", "No valid record found for class '$oclass' from $ymd1[0] to $ymd1[$m-1] on $tname.");
                  $warned = 1;
                  push @data ,'#';
                  last LOOP1;
                } else {
                  last LOOP1;
                }
              }
              @field = split(/ /, $rcd);
              if(scalar(@field) == 3 ) {   #for every 3 fields line Date Increment File
                ($sdate, $edate) = ck_date($field[0]);      #return yyyymmddhh
                $field[0] = substr($sdate, 0, 8);           # yyyymmdd format
                $field[1] = substr($edate, 0, 8);           # yyyymmdd format
                for($i=0; $i<$m; $i++) {   #looping through all ymd1
                  if($ymd1[$i]>=$field[0] && $ymd1[$i]<=$field[1] && length($field[2])>10) {
                    $data[$nrcd] = $field[2];
                    $nrcd++;
                    last;  #jump out this for loop
                  }
                }  #End of for($i=0; $i<$m; $i++)
              }  #End of if(scalar(@field) == 3 )
            }  #End of while( defined($rcd = <LUN>) )
          }   #End of if ($rcd =~ /BEGIN/i && $rcd =~ /$oclass$/)
        }  #LOOP1: End while( defined($rcd = <LUN>) )
        close(LUN) || die "Couldn't close file: $tname $!\n";
        if($nrcd <= 0) {
           if ($warned == 1) {
                     $warned = 0;
           }else{
                     msg("E", "Class name '$oclass' not found."); 
           }
        }

# Unique data
        @data = sort(@data);
        $m = 0;    $data1[$m] = $data[0];
        for($i=1; $i<scalar(@data); $i++) {
          if($data[$i] gt $data1[$m]) {
            push(@data1, $data[$i]);
            $m++;
          }
        }
        return($standard, @data1);
      }

#=========================================================================
#
# ck_date: subroutine to check and convert YYYYMMDD_HHz-YYYYMMDD_HHz(present)
#          and return with start, end in YYYYMMDDHH format
#
      sub ck_date {
        my($date_date) = @_;   #YYYYmmDD_HHz-YYYYmmDD_HHz(present)  HHz<24z
        my(@mday) = (31, 28, 31, 30,31,30,31,31,30,31,30,31);
        my($yyyy, $mm, $dd, $leap, $date, @arr, $m, $n, @d1, @t1, @x);

        if(length($date_date) <= 15) {msg("E", "WrongFormat: $date_date");}
        @arr = split(/-/, $date_date);
        $m = scalar(@arr);
        if($m != 2) {msg("E", "WrongFormat: $date_date");}
        for($n=0; $n<$m; $n++) {
          if($arr[$n] =~ /prese/i) {
            $d1[$n] = 'present';    $t1[$n] = '18';
          } else {
            if(length($arr[$n]) != 12) {msg("E","WrongFormat: $date_date");}
            @x = split(/_/, $arr[$n]);  #YYYYmmDD_HHz
            $d1[$n] = $x[0];          $t1[$n] = substr($x[1], 0, 2);
            if($t1[$n]>=24 || $t1[$n]<0){msg("E","WrongFormat: $arr[$n]");}
          }
          $date = $d1[$n];
          $leap = 0;      #regiular year
          if(length($date) <= 7 && $date =~ /pre/i ) { $date = $cdate; }
          if(length($date) != 8) {msg("E", "WrongDate:'$date' $rcd."); }
          $yyyy = substr($date, 0, 4);
          $mm   = substr($date, 4, 2);
          $dd   = substr($date, 6, 2);
          if($mm>12 || $mm < 1) {msg("E", "WrongDate:'$date' $rcd."); }
          if(($yyyy%4 == 0 && $yyyy%100 != 0) || $yyyy%400==0 )
          {$leap = 1; }
          if($mm == 2 ) {
            if($dd > ($mday[1]+$leap) || ($dd < 1)) {
              msg("E", "WrongDate:'$date' $rcd."); }
          } else {
            if($dd>$mday[$mm-1] || ($dd<1)) {
              msg("E", "WrongDate:'$date' $rcd."); }
          }
          $d1[$n] = $date*100 + $t1[$n];  #yyyymmddhh
        }
        return($d1[0], $d1[1]);
      }

#=========================================================================
#
# msg: subroutine to print out error and warning messages.  Exit the
#      software if the first input argument indicates an error "E".
#
       sub msg {
         my ($a, $b) = @_;
         $a =~ tr/a-z/A-Z/;
         print("-$a: $b\n");
         if($a =~ /^E/) { exit(1); };  # Exit for error
       }

#=========================================================================
sub usage {

   print <<"EOF";

NAME
     acquire_obsys - Makes an observation resource file and then calls acquire
                     script to retrieve these observation data from mass
                     storage with look-ahead capability

SYNOPSIS

     acquire_obsys [...options...]  bymd bhms ihms nstep obclass

DESCRIPTION

     Acquire is a general purpose utility for retrieving files from
     mass storage with a look-ahead spooling capability. The full path
     names of the files to be retrieved are specified in a resource file
     (see RESOURCE FILE below) by means of GrADS-like templates which
     will be generated by acquire_obsys.  For example, a resource file
     could specify a file name of the form:

      gatun:/silo3/dao_ops/conv+tovs/ods/Y%y4/M%m2/r4ods.t%y4%m2%d2_%h2z

     The following parameters are required on input:

     bymd     beginning year-month-day, e.g., 19980101
     bhms     beginning hour-min-sec, e.g., 120000
     ihms     time step increment in hour-min-sec format, e.g., 060000
     nstep    number of timesteps for time looping, e.g., 6.
     obclass  file class, e.g., conv_tovs, ers2, qscat, ssmi_wentz_tpw,
              ssmi_wentz_wind, sonde_hirs, and tovs_l1b etc.
              Note: You can enter multiple obclasses such as conv_tovs,ers2
              (no blank spaces and comma is the separator)

     For example,

         acquir_obsys 19980107 120000 060000 6 conv_tovs

     will generate the followings pairs of date/time

          nymd       nhms
         -------    -------
         19980107   120000
         19980107   180000
         19980108   000000
         19980108   060000
         19980108   120000
         19980108   180000

    For each one of these dates/time, acquire will expand the
    GrADS-like template and retrieve the corresponding files from
    mass storage. For the examples above, the files to be retrieved
    are:

    gatun:/silo3/dao_ops/conv+tovs/ods/Y1998/M01/r4ods.t19980107_12z
    gatun:/silo3/dao_ops/conv+tovs/ods/Y1998/M01/r4ods.t19980107_18z
    gatun:/silo3/dao_ops/conv+tovs/ods/Y1998/M01/r4ods.t19980108_00z
    gatun:/silo3/dao_ops/conv+tovs/ods/Y1998/M01/r4ods.t19980108_06z
    gatun:/silo3/dao_ops/conv+tovs/ods/Y1998/M01/r4ods.t19980108_12z
    gatun:/silo3/dao_ops/conv+tovs/ods/Y1998/M01/r4ods.t19980108_18z

    Upon transfer from mass storage, these files are made available
    at the user local directory (see "-d" option).

    The look-ahead capability allows the user to retrieve files for
    future use. For example,

         acquir_obsys -la 4 19980107 120000 060000 6 conv_tovs

    will generate 4 additional date/time pairs:

          nymd       nhms
         -------    -------
         19980109   000000
         19980109   060000
         19980109   120000
         19980109   180000

   and transfer the files
    gatun:/silo3/dao_ops/conv+tovs/ods/Y1998/M01/r4ods.t19980109_00z
    gatun:/silo3/dao_ops/conv+tovs/ods/Y1998/M01/r4ods.t19980109_06z
    gatun:/silo3/dao_ops/conv+tovs/ods/Y1998/M01/r4ods.t19980109_12z
    gatun:/silo3/dao_ops/conv+tovs/ods/Y1998/M01/r4ods.t19980109_18z

   to a spool directory. Next time the user issues an "acquire_obsys" to
   retrieve these files, they will already be available locally.
   For this "look-ahead" transfer acquire forks itself, performing
   this task in the background.

   Acquire is also smart enough to avoid retrieving the same file
   more than once. If in the example above we replace the file name
   template with

     gatun:/silo3/dao_ops/conv+tovs/ods/Y%y4/M%m2/r4ods.t%y4%m2%d2

   only the files

    gatun:/silo3/dao_ops/conv+tovs/ods/Y1998/M01/r4ods.t19980107
    gatun:/silo3/dao_ops/conv+tovs/ods/Y1998/M01/r4ods.t19980108

   would be retrieved.

OPTIONS

     -cp            when files are to be preserved in spool directory
                     (see -p) a copy is made to the user destination directory
                     (the default is to make a symlink)
     -d path        destination (local) directory (default: ./)
     -e logfile     name of error log file. (default: no logging enabled)
     -f             forces remote copy whether the file exists locally or not
     -h             prints this page
     -lfn           use long file names in spool directory to
                     prevent file name conflicts
     -la lstep      Look ahead lstep time steps, that is, future data
                     can be pre-fetched and kept in spool directory
                     (default: lstep=0)
     -p             preserve files in spool directory, simply making
                     a symlink() or copy to the local directory (see -cp);
                     this is useful if the file is expected to be reused.
                     In such cases one should monitor disk usage in the
                     spool directory.
     -s path        spool directory (default: /scratch1/$ENV{USER}/spool)
     -ssh           use ssh and scp (default: rsh and rcp)
     -strict        returns non-zero exit code if not all files
                     specified in the rc file are acquired
     -v             verbose mode (default is real quiet)
     -drc fullName  user specified database resource file with file path
                     (default: obsys.rc)
     -acqfile fullName  The path and filename of the generated acq file.
                        (the default path is the option "-d" and the
                         default filename is obsys.acq)

RESOURCE FILES

     The acquire_obsys will generate the resource file (with the file name
     as the_given_obclass_name.acq) by extracting records from the given
     obclass out of the observation database file which consists of
     information blocks for each obclass.
     Records defined by the obclass block show the remote file name template
     (will be used to form the resource file) and the time range (start/end
     date and time increment) which the remote file name template can be
     applied to.  For examp;e:

     BEGIN obclass
       startYYYYMMDD_HHz-endYYYYMMDD_HHz incrementHHMMSS remote_file_name_template
     END

     Acquire resource files consist of comment lines starting with
     '#' or a remote file name templates of the form

           rhost:path/fname

     This is better explained with an example:

     helios1:/u/joiner/tovs/l1b/%y4%m2/l1c_new/hirs.nj.hdf.t%y4%m2%d2

     In this example, the remote host (rhost) is "helios1", the path
     is /u/joiner/tovs/l1b/%y4%m2/l1c_new, and the fname is
     hirs.nj.hdf.t%y4%m2%d2.
     This file name "template" is a GrADS like pattern for matching
     remote file names (that is, files to be retrieved).
     Supported tokens are:

          %y4       year,  e.g., 1997
          %y2       year,  e.g., 97
          %m2       month, e.g., 12
          %d2       day,   e.g., 31
          %h2       hour,  e.g., 18
          %c        matches any character [?]
          %n        matches any single digit [0-9]

    In addition to GrADS-like tokens, any defined environment variable
    can be used in the remote file name template. For example,

     \${MHOST}:/u/joiner/tovs/l1b/%y4%m2/l1c_new/hirs.nj.hdf.t%y4%m2%d2

   would take the remote host name from the environment variable \$MHOST.

SEE ALSO

    acquire - Retrives files from mass storage with look-ahead capability

AUTHORS

     Eueng-nan Yeh (enyeh\@dao.gsfc.nasa.gov)

EOF

  exit(1)
}