Re: [Help-smalltalk] How to access environment variables ?

[Mehul N. Sanghvi]

Krishna said the following on 02/10/2009 09:50 AM:
> On Tue, Feb 10, 2009 at 8:11 PM, Krishna <address@hidden> wrote:
> > On Tue, Feb 10, 2009 at 8:03 PM, Paolo Bonzini <address@hidden> wrote:
> > > Krishna wrote:
> > > > On Tue, Feb 10, 2009 at 7:41 PM, Paolo Bonzini <address@hidden> wrote:
> > > > > > There are extra shell variables showing up like PATH, BASH, TERM, etc.
> > > > > > which do not show up in a CGI environment using any other language that
> > > > > > I've used to write a similar CGI program (Perl, PHP, Lisp, Scheme, C,
> > > > > > Tcl).  All of them print out the same variables as the output of the
> > > > > > Perl script.  What we seem to  be doing in Smalltalk is forking/execing
> > > > > > a shell and and then getting the environment variables so that we end up
> > > > > > with variables from a hybrid environment of CGI and shell.
> > > > why not call getenv(3) using the C interface?
> > > He wants *all* the variables, not just one.
> > ha! ok. is it possible to build a custom gst with int main(int argc,
> > char** argv, char** envp) and slurp the environment from there?
>
> unistd.h defines char** environ. exporting that to smalltalk should
> solve the problem right?


That would work with GNU C library since it is defined as follows:

/* NULL-terminated array of "NAME=VALUE" environment variables.  */
extern char **__environ;
#ifdef __USE_GNU
extern char **environ;
#endif

I'm not sure how it is defined on other Unix systems.  On Solaris 9 it doesn't 
exist in /usr/include/unistd.h:

Solaris-9% grep environ /usr/include/unistd.h
/* large file compilation environment setup */
/* In the LP64 compilation environment, the APIs are already large file */


So although I could probably make use of it, I'd break portability of GST along 
with what ever I am working on.

This is my quick and dirty assessment of it.  I have not looked at GST code 
ever yet so far.  This is based on just looking at the include files on Linux 
and Solaris 9.  I could be interpreting things incorrectly.


cheers,

    mehul