getenv - get value of environment variables
subroutine getenv (ename, evalue)
character*(*) ename, evalue
The getenv subroutine searches the environment list (see
environ(5)) for a string of the form ename=value and returns
value in evalue if such a string is present; otherwise, it
fills evalue with blanks.
libF77.a
execve(2), environ(5)