The ENVIRON$ function returns the value assigned to an operating system environment variable. You may choose which environment variable to read in one of two ways. If you know the name of a variable, you can specify it by name and its definition will be returned. If the variable does not exist or if the definition is blank, a zero length string is returned. You can also specify a number, in which case both the corresponding variable, an equal sign and the definition are returned. The first variable is number 1. The names of environment variables are case insensitive.
BackPorting to HP BASIC:
ENVIRON$ is a new HTBasic function that is not available in HP BASIC. It should not be used in programs that must be ported back to HP BASIC.
