インテル® Fortran コンパイラー XE 13.1 ユーザー・リファレンス・ガイド
POSIX Subroutine: Clears the process environment.
USE IFPOSIX
CALL PXFCLEARENV (ierror)
ierror
(Output) INTEGER(4). The error status.
If successful, ierror is set to zero; otherwise, an error code.
After a call to PXFCLEARENV, no environment variables are defined.