You need to print out all the other lines also.

If you want to edit a line and leave it in the file then just get rid of the if.

...
foreach (@dat)
{
  s/number/NEWWORD/;
  print DATA $_;
}
close(DATA);

[download]

This will change the lines that need changing and print everything into the file.

There is another risk with this method that if the program dies before getting the file printed back out your original file which was erased on the second open will not have the complete data. This is what the backup options cover you against.

This will do the translation and leaves a backup file in this case named file.txt.bak.

perl -pi.bak -e 's/number/NEWWORD/;' file.txt

[download]

The -p says to print every line, the -i.bak says make a backup file by adding .bak to the input file name, -e says to run the next argument as a perl script. The substitute only happens if the pattern matched so there is no need for an if unless you want to locate one pattern and then replace another pattern with yet a different replacement.

In reply to Re: Re: Re: Deleting a line out of text file by dga
in thread Deleting a line out of text file by Anonymous 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.