There are three commonly proposed methods to do this:

Read the entire file 

@array = <FILE>;
$last_line = $array[$#array];

[download]
This involves reading the entire file before examining the last line, which can be costly in memory and performance for large files.

Seek to the end and backtrack 

seek(FILE, -81, 2);             # 81 bytes from the end, which should 
+be enough
@lines = <FILE>;
$last_line = $lines[$#lines];   # similar to above, but we don't read 
+much

[download]
Use File::ReadBackwards 
tie *FILE, File::ReadBackwards 'input_file';
while (<FILE>) {
   # line-by-line starting from the end
}

[download]
This latter method is supposed to be efficient and fast, so I imagine it uses some variation of the seek() method above.

In reply to Re: How do I copy out the last line written in a file? by Fastolfe
in thread How do I copy out the last line written in a file? by Anonymous Monk

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