On OSX El Capitan I had to use
mysqld -initialize --verbose --user=whoami --basedir="$(brew --prefix mysql)" --datadir=/usr/local/var/mysql --tmpdir=/tmp
whoami
instead of
mysqlinstalldb --verbose --user=whoami --basedir="$(brew --prefix mysql)" --datadir=/usr/local/var/mysql --tmpdir=/tmp
for the long command. Otherwise I got the [ERROR] unknown option '--tmpdir' too
On OSX El Capitan I had to use
mysqld -initialize --verbose --user=
whoami--basedir="$(brew --prefix mysql)" --datadir=/usr/local/var/mysql --tmpdir=/tmpinstead of
mysqlinstalldb --verbose --user=
whoami--basedir="$(brew --prefix mysql)" --datadir=/usr/local/var/mysql --tmpdir=/tmpfor the long command. Otherwise I got the [ERROR] unknown option '--tmpdir' too