The other advantage of fixed size buffers is if you want to write the records to disk you can just write it directly. You don't need to serialize or instantiat

The other advantage of fixed size buffers is if you want to write the records to disk you can just write it directly. You don't need to serialize or instantiate the strings when reading, you can just copy the bytes straight to or from the file. Looking at things like man utmp.5 should reveal what their thinking was.