Initialise a new database cluster

I create new db clusters just infrequently enough that I never remember the flags I use when creating the cluster. In this example, I create a database using the SQL_ASCII character encoding (which is sort of the non-character-encoding character encoding, as opposed to, let's say, UTF8 or LATIN1) and collating/sorting based on the C locale, which is the "no locale" (as opposed to, let's say, en_US or fr_CA):

initdb \
    --pgdata=/u1/pg/data \
    --encoding=SQL_ASCII \