I have a text file as follows:

line 1
line 2
line 3
line 4

I am trying to figure out how to modify the text of say line 2 in the above example. I don't want to read and then write a line to a temp file because while I may be running this script to modify line 2, someone else may be running it to modify line 1. In other words, I am looking for a way to modify the file in place if the content of a line equals say for instance "line 2".

Consider this psudo code as it doesn't quote work:
use strict;
my $file;
$file="/text_file.txt";
open (FILE,"+<$file");
while( <FILE>) {
  if ($_ =~ /line 2/i) {
    print FILE "replacement text\n";
  }
}
close FILE;

[download]
After reviewing other posts, perhaps I am in need of the seek command?

In reply to Modifying lines of text by Anonymous Monk

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