vi is pronounced as the two separate letters, /ˌviːˈaɪ/ (in English); listen to the same Brian Kernighan (also re-confirming the
Vim’s pronunciation is explicitly documented:
Vim is pronounced as one word, like Jim, not vi-ai-em.
Nemo mentioned this interesting email about “Unix-room” pronunciations from Rob Pike, which includes a number of interesting tidbits in relation to this question:
- some Unix-room denizens did pronounce
ed like the first syllable of “editor”;
vi was little-used but apparently pronounced /ˌviːˈaɪ/ by all its users;
- on Plan 9,
vi was a MIPS interpreter (“v” for MIPS, along with “5” for ARM, “k” for SPARC, and “q” for PowerPC), also pronounced /ˌviːˈaɪ/.
vi came from BSD, not the Unix room, so Unix-room pronunciation isn’t necessarily canonical (if there is such a thing anyway in a living language). But Mark Plotnick’s answer gives a reference from
vi’s creators themselves.