SQLite Forum

Unicode and CLI for Mac
That would seem to indicate that the shell requesting (or that the OS has set) a "cooking mode" on SYSIN which is not being respected or maintained when the SYSIN input stream is inherited by the sub-process (sqlite3) and that sub-process is operating in "interactive" mode.

If you use the command `sqlite3 -batch` does it work properly (note that -batch will not present you with a prompt but will instead use a reduced "best user interface ever invented, by Ashton-Tate, without even the horror of a dot").

It will also use the SYSIN stream as-is and not try to set or unset any cooking.