Guys would have to put a custom environment parameter named "PS1" into a profile document in order to modify current Terminal prompt.
It'd be done for nothing as you try to touch .bash_profile at user directory "~", as well as modifying the /etc/profile by appending a line, such as export PS1='[\t \w] \$ ', which will be denied resolutely.
This problem can't be solved by adding your current user into the "read & write" privilege group in terms of the file you want to alter.
But it's a workaround to bypass the limitation by editing the /etc/profile in vi/vim.
export PS1='[\t \w] \$ ' will be accepted by entering a ":wq!" instruction.
Take note of the exclamation mark which will force the content to be saved into the hard drive.
At last, you'll continue to type source /etc/profile in order to put the latest setting into operation.
Preference
