Before I go off and write a new one, does anyone know of a good command line disk partition utility that works better than "parted"?

cfdisk?

For actually making filesystems, mkfs.{ext3,ext4,xfs,jfs} etc. are standard and well documented.

I guess I didn't say it just right.

What I am looking for is an "all in one command" way of partitioning. All the info should be given on the one command line, in arguments. Giving the info as stdin can be OK, but it needs to be in a sensible form that a script does not have to do calculations for. I'm hoping for something smart enough to figure out partition positions for me, given minimum sizes, and position on a specified alignment (such as multiples of 2048 sectors ... disregarding legacy CHS we no longer need). It needs to support both MBR and GPT. I would be running it from a script or program.

I don't need any filesystem formatting steps in this. Those would be done later.

I haven't used it yet, but you could check out if
man sfdisk

does what you need. May I ask, what you do not like about parted?

Yes, I was also going to suggest sfdisk is the usual batch utility. Wouldn't do all you want, but you should be able to script around it for DOS MBR type disks. gpt would be a problem though.

I'm already using sfdisk. And it is very cumbersome to script around. That's why I'm looking at writing my own program to do formatting. But I wanted to be sure I was not re-inventing a more rounded wheel.