How big was the original CP/M version of WordStar? As in, the size of the program itself? Presumably it was in the low tens of kilobytes (I don't think it's possible to cram a practical word processor into less than 10K) but I'm interested in an actual figure.
The oldest version I have disk images for is 0.87 and the file sizes are: (although the WSU.COM creates WS.COM files that crash to the > prompt)
WSU.COM 29696 (the install program is embedded into the WSU.COM file) WSMSGS.COM 14464
The earliest version I have that the install works is 0.93 and those files sizes are:
INSTALL.COM 16128 WSU.COM 29568 WSMSGS.COM 19328 OVERVIEW.WS (or EXAMPLE.TXT) 13440
Also WordMaster (basically a text editor) and WordStar (a word processor) are not the same program, so you can't compare the two as far as the sizes go. WordStar succeeded WordMaster. Both were written by John Robbins Barnaby.
How big was the original CP/M version of WordStar?
The oldest copy of WordStar (or Wordmaster) I could find is 1.01 (but with a date of 1980) sizing
30,080 bytes for WS 20,992 bytes for WSMSGS
Which both seem rather high, as Wordmaster, before being renamed to WordStar, did fit into mere 10 KiB. One of the core features of WordStar was its organization as overlays, thus the used memory might be lower.
I don't think it's possible to cram a practical word processor into less than 10k
That might quite depend on your value for 'practical'. I can quite well think of a full screen word processor that can be cramped in way less than 10 KiB. As said, Wordmaster is just 10 KiB. And DR's TEX (where Wordmaster is somewhat based on) only uses 8 KiB.
It's worth to keep in mind that even professional machines at the time (pre 1980) often only hat 16 KiB of RAM - full 64 KiB was rather rare. So size was even more a goal.
Ofc RAM could be saved by making machine specific version using existing ROM routines (CP/M didn't really offer much here) - even more so by using a Program ROM. Examples may be:
- Word Processor Pac, an 8k ROM for the Exidy Sorcerer (*), a custom version of Spellbinder
- Wordwise, an 8k EPROM for the BBC Micro (*)
- Texor, an 8k Module (M012) for the Robotron KC-85 series
History repeated (somewhat) with home computers and their small memory. A great example might be SpeedScript for C64 and VC-20. While needing an 8 KiB RAM expansion on the VIC (VIC-1110), the program itself was only about 5 KiB, leaving 3 KiB for text (The other 5 KiB were needed vor variables, screen and text buffer).