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

Hi, I need a help with renaming files which begins "sniffer" in directory. 
opendir(DIR, '.') || die "Couldn't opendir: $!\n";

foreach my $filename (reverse((grep /^sniffer/, readdir(DIR)))) 
{
    my $new_name = $filename;    
    if($new_name =~ m/(\d+)/)
    {
        my $value = $1 +1;        
        $new_name =~ s/.*/"sniffer$value\.log"/;          
    }
    else
    {
        $new_name =~ s/.*/sniffer1.log/;
    }
    rename($filename, $new_name) unless $filename eq $new_name;    
    close(DIR);

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My aim is to increment number in files which begin "sniffer". In example: sniffer.log will be sniffer1.log, sniffer1.log will be sniffer2.log, etc. The oldest file (with the highest number) must be changed at the beginning - this is the reason of using reverse function in foreach loop.

Unfortunately I received this error: 

Insecure dependency in rename while running with -T switch at ...

[download]

If anyone knows the solution of this problem or the easiest way how to increment files number ?

Thanks in advance ;)

Replies are listed 'Best First'.
Re: Problem with renaming files in directory
by Ratazong (Monsignor) on Jan 03, 2012 at 15:40 UTC

    Not related to the error-message you get. But why do you use 

    $new_name =~ s/.*/sniffer1.log/;

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    instead of 
    $new_name = "sniffer1.log";

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    And why do you close DIR inside the foreach-loop?

    Rata (scratching his head)
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Re: Problem with renaming files in directory
by toolic (Bishop) on Jan 03, 2012 at 15:50 UTC
    If I don't use the -T switch on my shebang line, the script renames files without that error. Do you really need -T (perlsec)?

    Also, I get quotes in the file names. To avoid that, you should change: 

    $new_name =~ s/.*/"sniffer$value\.log"/;

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    to: 
    $new_name = "sniffer$value.log";

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    Also, readdir may not return the order you expect if you have double digits.
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      ok, thanks for replies guys :) Right now my code is: 
      foreach my $filename (reverse((grep /^sniffer/, <*>))) 
{
    my $new_name = $filename;
    
    if($new_name =~ m/(\d+)/)
    {
        my $value = $1 +1;        
        $new_name = "sniffer$value.log";          
    }
    else
    {
        $new_name = "sniffer1.log";
    }
rename($filename, $new_name) unless $filename eq $new_name;
    
}

      [download]

      I didn't run with -T switch and I have all the time the error. Do you have any other hints ? :)

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[d/l]
        Using diagnostics reveals this info: 
        Insecure dependency in rename while running with -T switch at 
    (F) You tried to do something that the tainting mechanism didn't l
+ike.
    The tainting mechanism is turned on when you're running setuid or
    setgid, or when you specify -T to turn it on explicitly.  The
    tainting mechanism labels all data that's derived directly or indi
+rectly
    from the user, who is considered to be unworthy of your trust.  If
+ any
    such data is used in a "dangerous" operation, you get this error. 
+ See
    perlsec for more information.
    
Uncaught exception from user code:
        Insecure dependency in rename while running with -T switch at

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        Since you are not explicitly using -T, look into setuid or setgid.

        By the way, changing readdir to glob will not solve the double-digit filename issue.

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