Hi,
My program asks the user to enter the name of the file and the parameter to be changed in that file from the command line.
$ perl comm.pl -f test-file -p <new value>

The test-file contents are of the form :

<PROP GUID="471138786526914052" EXPR="≪E The_Rounding_Unit=&Quot;1e-16&Quot; Absolute_Error_Tolerance=&Quot;1e-15&Quot; /&Gt";"/>

Iam posting a part of the code which replaces the old value 1e-16 (which is stored in this form &Quot;1e-16&Quot;) with the <new value> entered by the user and then renames the file with the timestamp. I can't figure out where iam going wrong. Does the command line accept more than 2 switches with values ? i have used Getopt::Long module. Please help me out. 
if ($var{file}) #the test-file name entered by user
{
 my $fname=$var{file};
 unless ($fname) { die ("No file specified.\n"); }
 unless (-e $fname) { die ("File does not exist.\n");}
 my $line;
 open (INFO,"$fname") or die ("Cannot open .. $!\n");
 while (<INFO>)
{
  $line=<INFO>;
}  
close INFO;  
  my @new2;
  if($var{param}) { list_param($var{param}); }
  if($var{the})   { list_the($var{the}); }

sub list_param($)
{        
   if ($line =~ m:Absolute_Error_Tolerance=&quot:)
      {
          @new2=split(/\&quot;/,$line);
          $line=~s/$new2[1]/$G{param}/;
       }
}
sub list_the($)
{
      if ($line =~ m:The_Rounding_Unit=&quot:)
       {
          @new2=split(/\&quot;/,$line);
          $line=~s/$new2[1]/$G{the}/;
       }
}
my $timestamp = strftime("%m/%d/%Y_", localtime((stat($var{file}))[9])
+);
my $file2=$timestamp.$var{file};
rename ($var{file},$file2) or warn "***\n";
}

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In reply to using command line switches to edit file by kitty

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