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8.10. Removing the Last Line of a File
8.10.1. Problem
You'd
like to remove the last line from a file.
8.10.2. Solution
Use the standard (as of v5.8) Tie::File module and delete the last
element from the tied array:
use Tie::File;
tie @lines, Tie::File, $file or die "can't update $file: $!";
delete $lines[-1];
8.10.3. Discussion
The
Tie::File solution is the most efficient solution, at least for large
files, because it doesn't have to read through the entire file to
find the last line and doesn't read the entire file into memory. It
is, however, considerably slower for small files than code you could
implement yourself by hand. That doesn't mean you shouldn't use
Tie::File; it just means you've optimized for programmer time instead
of for computer time.
8.10.4. See Also
The documentation for the standard Tie::File module; the
truncate and tell functions in
perlfunc(1) and in Chapter 29 of
Programming Perl; your system's
open(2) and fopen(3)
manpages; Recipe 8.18
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| 8.9. Processing Variable-Length Text Fields |  | 8.11. Processing Binary Files |
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