Shell Programming and Scripting

 
#!/usr/bin/perl
 
($ProgName = $0) =~ s%.*/%%;
print STDOUT "Enter the number of segments to split\n";
$splitnum = <STDIN>;
chomp($splitnum);
if ($#ARGV>0) { print STDERR " *** One file at a time, please!\n", exit 1; }
if ($#ARGV<0) { print STDERR " *** Sorry, need a filename!\n", exit 1; }
print STDOUT "\n$ProgName: Beginning $splitnum way split on $ARGV[0]\n\n";
open INFILE, "<$ARGV[0]" or die "\n$ProgName: *** Can't open data file '$ARGV[0]': $!\n\n";
while (<INFILE>)
 {
  $counter++;
  if ($counter%100000 == 0) { print "$counter\n"; }
  my $seg = substr($_,376,2);
  my $key = substr($_,392,25);
  chop($key);
  $a = 1;
  while($i<=$splitnum)
   {
    $oflename = "OFLE$key";
    open $oflename, ">$ARGV[0].$key.dat" or die "\n$ProgName: *** Can't open data file '$ARGV[0].$key.dat'";
    if ($a <~ m/10/i) { $b="0$a"; if ($seg =~ m/$b/i) { print $oflename; } }
    if ($a >=~ m/10/i) { if ($seg =~ m/$a/i) { print $oflename; } }
    $a++
   }
 }

awk '!/^$/{
key=substr($0,393,25)
print $0 > key".dat"
}' testmail.dat

       read FILEHANDLE,SCALAR,LENGTH,OFFSET
       read FILEHANDLE,SCALAR,LENGTH
               Attempts to read LENGTH characters of data into variable SCALAR
               from the specified FILEHANDLE.  Returns the number of
               characters actually read, 0 at end of file, or undef if there
               was an error (in the latter case $! is also set). 

-- excerpt from perldoc -f read