Created attachment 178593 [details]
diff to mbsrtowcs.3
It's not clear from the man pages of several multi-byte and wide character functions that, if you pass NULL as the destination, they return the number of characters that would have been written where dst an actual array. I attach a diff to fix one of them.
I haven't done others because:
a) I need to confirm which ones this is true for
b) I wasn't sure how great my wording was.
If someone who knows more about this than I wants to make similar changes to other man pages then that is great. Otherwise, once final wording is decided upon, I might get time to test and submit more.
I am using 11-stable r310981