Final words on style
It is easy to support pre-ANSI-Standard compilers in most programs, so if you know how to do that and a program you are maintaining has such support, you should try to keep it working.
Whatever style you use, use it consistently. A mixture of styles within a single program tends to look ugly and be hard to read and maintain. If you are contributing changes to an existing program, it is best to follow the style of that program.