Delete last line from a file?

[Ravenous]

How to? I've got a script parsing through a tab-delimited text file and converting it to a format as specified by an investment securities company. The script tacks a "\n" to each line to (Who'da guessed?) start a new line. How can I remove the last newline? There will be a variable number of lines in this file so I can't just use a count control for it. I figure it would be easiest to delete the last line as a final, quick little command.

So yeah, how to? Thanks.

[drew010]

sorry, i lost clarity toward the end, do you want to remove the entire last line i.e.
data data data\n
or the last newline '\n'
?

[Ravenous]

I wanna turn

data data data
data data data

into

data data data
data data data

.
So I want to remove the last "\n".

Sorry for the lack of clarity.

[Weedpacket]

Is the newline character always going to be there?
$line=substr($line,0,-1);