I was under the impression that

String#encodeToByteArray

would add a null terminator, since it’s used by cstr, however, this does not appear to be the case. Should I manually add

0.toChar()

to each string I need to pass to C? I also noticed that ‘\0’ is not valid in Kotlin, saying it’s an illegal escape.

Kotlin doesn't have octal escapes, only hex unicode escapes (and a few named escapes). NUL char is

\u0000