Accessing variables from inside a C-XS

Hi,

I'd like to access a Perl-variable (a scalar) from within an XS. I do
accept that the scalar may not (yet) exists, so I'd cater for that:

if (var_exists("$scsi_timeout"))
    timeout = strtoul(..., &next, 0);
else
    timeout = DEFAULT_TIMEOUT;

How do I do that:
- find out if a scalar exists
- access the contents of the scalar.

Josef
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Josef Möllers (Pinguinpfleger bei FTS)
	If failure had no penalty success would not be a prize (T.  Pratchett)
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