ruby - rbenv installation permission denied -

hi i'm trying set dev environment , i've been following tutorial via; link tutorial

i'm not doing , have no real experience of terminal commands other basic version control stuff. followed first link , when trying run

source ~/.bash_profile 

i got error; mkdir: /usr/local/rbenv/shims: permission denied mkdir: /usr/local/rbenv/versions: permission denied

now every time load terminal error appears.

contents of bash_profile;

export path=/usr/local/rbenv/bin:$path export rbenv_root=/usr/local/rbenv eval "$(rbenv init -)" 

any guidance appreciated

it looks rbenv setup puts line of shell scripting in .bash_profile attempts create directory. either give permissions create directories in /usr/local/rbenv, or sudo mkdir /directories/that/need/to/be/created once.

sudo mkdir -p /usr/local/rbenv/shims sudo mkdir -p /usr/local/rbenv/versions