Even with this approach you still would need locking.

Yes, as written. But the ">>" file mode does allow you to use something very similar to this without (additional) locking. 

use IO::Handle;
my $filename = '/path/to/file';

# Increment the counter (atomically, so no locking required)
open(FILE, ">> $filename") or warn "Missed a count";
FILE->autoflush(1);
print FILE '.';    # Ouput one (arbitrary) byte
my $counter= tell(FILE);
close FILE;

[download]

Now, if you reset your counters every so often, this can be a really nice little trick. To reset the counters, just do a unlink($filename) once a day/week/month, which also doesn't require any locking on your part! (Though the location and permissions on the counter file are a non-trivial problem so you may want to use sysopen so you can specify permission bits for the case when the file is recreated.)

        - tye (but my friends call me "Tye")

In reply to (tye)Re: Flock Feedback by tye
in thread Flock Feedback by footpad

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.