Not needed, because you'll be the only one creating the temp file if you make it that far. And no, there's no module at the moment that does this just like this. Odd that you should say that, because I was thinking of making a small module to do just that. Interface would be something like: 
use File::UpdateExclusively;
{
  my $handle = File::UpdateExclusively->on("/some/file/name") or die;
  my @data = <$handle>;
  ## process @data
  print $handle @data;
}

[download]
The return value would be a tied handle. Reading from the handle would read from the beginning of the original file (now flocked). Writing to the handle writes to the new location. Closing the handle or letting it go out of scope does the rename shuffle.

Now to code that... {grin}

-- Randal L. Schwartz, Perl hacker

In reply to RE: $$, perhaps? by merlyn
in thread Exclusively updating a file that continues to be repeatedly read by merlyn

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.