The amount of code required to accomplish this task depends greately on what kind of file he's dealing with. Using one file instead of two is not always simpler/easier to code.

If files that you're dealing with are small; i.e., config files, etc., it's probably easier to slurp them into memory, perform modifications, truncate the file, and then write data back -- no temp files needed.

With larger files and variable-length records, it's easier to work with temp files. If you attempt to update a variable-length record file without having a temp file, the code will get very ugly in no time. Sometimes, however, you just have to bite the bullet and do it; i.e., when you deal with huge files and you can't spare space for a temp file of the same size.

If you're working with large fixed-length record files, it is almost always better and more elegant, in my opinion, to work with the original file without creating temp files.


--perlplexer

In reply to Re: Replacing a string in a file by perlplexer
in thread Replacing a string in a file by Avi

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.