cat form.tmp
#username=MYUSER&password=MYPASS
#^-- wget may require no newline
# | tr -d '\n'
wget -O/dev/null \
    --keep-session-cookies \
    --save-cookies ninjacookie.txt \
    --post-file form.tmp \
    https://ninjastrike.com/dologin
wget -O- \
    --load-cookies ninjacookie.txt \
    https://ninjastrike.com/
curl --cookie-jar ninjacookie.txt \
    --data @form.tmp \
    https://ninjastrike.com/dologin
curl --cookie ninjacookie.txt \
    https://ninjastrike.com/