putenv
======

POSIX specification:
 https://pubs.opengroup.org/onlinepubs/9699919799/functions/putenv.html

Gnulib module: ---

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Extension: Gnulib provides a module putenv that substitutes a putenv implementation that can also be used to remove environment variables.