[Lazarus] SetEnv on Linux 64bit

[Honza]

2012/4/3 Michael Van Canneyt <michael at freepascal.org>:
>
>
> On Tue, 3 Apr 2012, waldo kitty wrote:
>
>> On 4/3/2012 09:57, michael.vancanneyt at wisa.be wrote:
>>>
>>> On Tue, 3 Apr 2012, fred f wrote:
>>>>
>>>> I need to set up LIBOVERLAY_SCROLLBAR=0 on Ubuntu 64bit, but there LIBC
>>>> is not
>>>> supported and therefore I am looking for SetEnv which I can use on 64bit
>>>> Linux.
>>>>
>>>> SysUtils contains only GetEnvironmentVariable, but not Set...
>>>
>>>
>>> That's not how it works on Unix/Linux.
>>>
>>> You must always set up environment variables before a program starts.
>>> When starting a process, the environment for that process is started and
>>> is
>>> then immutable for the duration of the process.
>>
>>
>> ewww... so no "fancy" capabilities like we could do in the old DOS days
>> where we could change the base environment as well as cloning it with
>> changes for child processes??? if so, that's blows several of my porting
>> projects up :? :(
>
>
> Not possible on Posix platforms.

Now I'm confused. AFAICS
(http://pubs.opengroup.org/onlinepubs/007904975/functions/setenv.html)
Posix setenv() allows a process to mutate its environment variables.

I probably misunderstood something, can someone enlighten me please?

-- jan