204494 - Provide PR_UnsetEnv()

Status: NEW

(NSPR :: NSPR, enhancement)

Description

[Kenneth Herron]

NSPR provides a function called PR_SetEnv() to create/change an environment
variable. However, there's no documented method for removing a variable from the
environment.

prenv.h notes correctly that the string passed to PR_SetEnv() must be
persistant, because the function can be implemented through putenv() which
incorporates the original buffer into the environment. This is true even if the
buffer contains "NAME=", i.e. the caller is attempting to invalidate the envvar.

This is a problem for a module that wants to create an environment variable and
then remove it later. After creating a variable the buffer containing the
variable can be swapped for a new one, but there's no way to completely withdraw
memory controlled by the module from the environment, e.g. as a prelude to
unloading the module from memory. See bug 194761 comment 7 and later for a
module affected by this.

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

The bug assignee is inactive on Bugzilla, so the assignee is being reset.