Today I found the task to change all occurences of a string in some of a larger sum of files and remembered perlrun, which I don't do very often. After having backupped all files in question (which proved to be a good idea later), I did a

perl -pi -e 's/(:Timeplaner):Projekt,/$1$1,/' *

and naively expected it to change the 115 (out of 432) files that needed the change.

But of course it did more than just that.
All files were changed, and their old access date was lost (read: except for in the backup, d'oh!).

Now I am wondering what would be the nicest way of doing the task to only change those files actually containing the string I am looking for, leaving the others untouched and still use something comparatively simple as   perl -pi?

Cheers, Sören

In reply to "Change, but don't touch" or naive use of perl -pi by Happy-the-monk

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.