Remove variable or function names
SYNTAX unset [-fv] [name] OPTIONS -f The names refer to shell functions, and the function definition is removed. Readonly variables and functions may not be unset. -v Each name refers to a shell variable(default)
The return status is zero unless a name does not exist or is readonly.
uset is a BOURNE shell command and a POSIX `special' builtin.
env - Display, set, or remove environment variables
echo - Display message on screen
export - Set an environment variable
function - Define Function Macros
readonly - Mark variables/functions as readonly
set - Manipulate shell variables and functions