Re: Doc--protecting guile entities defined in C

[Christopher Cramer]

On Mon, Jun 02, 2003 at 10:46:58PM +0200, Pascal Cedraschi wrote:
> I have tried defining a global (in C) SCM variable
> and setting the symbol's name with `scm_str2symbol' but the symbol thus
> defined disappears unless I protect it (from the garbage collector?)
> with `scm_gc_protect_object'.  Is that right?

That is correct, although I think in most cases you should instead use
scm_permanent_object. scm_gc_protect_object should be used when you might
end up using scm_gc_unprotect_object later. The usual way of creating
a static symbol in C is:

        foo = scm_permanent_object(scm_str2symbol("foo"));

Basically whenever you store a Scheme value (whether a symbol or any
other data type) that isn't on the stack, you need to protect it.
Apparently, this isn't in the manual.

-- 
Christopher Cramer <address@hidden> <http://www.pyro.net/~crayc/>
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