How can I remove the last character of a file in unix?

Question

Say I have some arbitrary multi-line text file:

sometext
moretext
lastline

How can I remove only the last character (the e, not the newline

Answer 1

After a whole bunch of playing around with different strategies (and avoiding sed -i or perl), the best way i found to do this was with:

sed '$! { P; D; }; s/.$//' somefile