VMS/IRAF Installation and Site Manager's Guide
VMS/IRAF Installation and Site Manager's Guide
Since IRAF is a machine and operating system independent, distributed system
capable of executing on a heterogeneous network, it has its own environment
facility separate from that of the host system. Host system environment
variables may be accessed as if they are part of the IRAF environment (which
is sometimes useful but which can also be dangerous), but if the same
variable is defined in the IRAF environment it is the IRAF variable which
will be used. The IRAF environment definitions, as defined at CL startup
time, are defined in a number of files in the [IRAF.VMS.HLIB] directory.
Chief among these is the system wide zzsetenv.def file. Additional
user modifiable definitions may be given in the user's login.cl file.