help related to modifiaction of read only value attempted error

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

I am having a code shown below. this procedure is called as
Infile($filename)
where $filname contains a name of file. i am getting folowing error
Modification of a read-only value attempted at testscript1.pm at line line #(some number).
see the code i had written a comment where error comes. this is first place i am using $status scaler. Ca any one tell what is reason for this. when i change name of $status to $statu , no error comes.

sub InFile
{
   
   local($outfile) = @_;
   
   if( -e $outfile)
   {
    if( open(SRC_FILE, $outfile))
    {                          
        open(DEST_FILE, ">TEMPFILE_TOPLOG");
        local($date1) = scalar localtime();
        print DEST_FILE (@header);
        print DEST_FILE ("*** Log generated on $date1\n");
        
        $line = <SRC_FILE>;
        while($line ne "")
        {       
        print DEST_FILE ($line);            
            $line = <SRC_FILE>;
        }
        close(DEST_FILE);
        close(SRC_FILE);
        
       
        local($filename1) = "TEMPFILE_TOPLOG";
        local($newfile) = $outfile;

$status = system("mv $filename1 $newfile");# HERE ERROR COMES
        if ($status != 0)
        {
print "FAILED WHILE MOVING mv $filename1$newfile\n";
            return 1;
        }
    } 
    else
    {
    print "FAILED WHILE OPENING  $outfile\n";
        return 1;
    }
    }
    return 0;    
}
[download]

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Comment on help related to modifiaction of read only value attempted error Download Code

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Re: help related to modifiaction of read only value attempted error by chromatic (Archbishop) on Mar 01, 2005 at 07:57 UTC
It's not obvious from the code you posted. However, I will guess that if you used my instead of local on your variables as appropriate, you'd clear up the error. Try this line instead: `my $status = system("mv $filename1 $newfile");` Of course, I'd write that code as: `unless (system("mv $filename1 $newfile") == 0) { print "FAILED WHILE MOVING mv $filename1$newfile\n"; return 1; }` [download] That avoids the variable altogether. Another suggestion is to look into the module File::Copy and the operators unlink and rename, so as to avoid unnecessary system calls.	[reply] [d/l] [select]
Re: help related to modifiaction of read only value attempted error by tphyahoo (Vicar) on Mar 01, 2005 at 09:57 UTC
You should also put `use strict; use warnings;` [download] at the top of your code.	[reply] [d/l]