[fpc-pascal] Setting environment variables on Unix/Linux?

[michael.vancanneyt at wisa.be]

On Thu, 17 Nov 2011, Reinier Olislagers wrote:

> Hi list,
>
> It seems FPC allows one to retrieve environment variables on Linux/Unix
> (GetEnvironmentVariable) but not to set them.
>
> Is that correct?

Yes.

>
> Some digging:
> Setting environment variables on Unix with gnu libc:
> http://www.gnu.org/s/libc/manual/html_node/Environment-Access.html#Environment-Access
> int setenv (const char *name, const char *value, int replace)
> The setenv function can be used to add a new definition to the
> environment. The entry with the name name is replaced by the value
> ‘name=value’.
> If replace = 1, replace existing variable.
>
> This one seems not to be present in FPC libc code
> Maybe something like (taken from netware source\rtl\netwlibc\libc.pp):
> function setenv(_para1:Pchar; _para2:Pchar;
> _para3:longint):longint;cdecl;external clib name 'setenv';

No. Unix works differently.

Environment variables are specified on startup, and are then immutable.

If you want to specify the environment for a process, you must do it at the
start.

Michael.