This is by far the best explanation of symbols I’ve read, ever. Thanks!
> On 22 Feb 2024, at 13:41, Christof Ressi <[email protected]> wrote: > > Hi, > > Pd symbols are immutable and permanent. `gensym("foo")` looks if the symbol > "foo" already exists; if yes, it just returns it, otherwise it creates a new > symbol, adds it to the global symbol table and finally returns it. > > You must never attempt to free a symbol! > >> ``` >> t_symbol **x_weights_arrays; >> t_symbol *x_biases_array; >> ``` > Here you must only free `x_weights_array`, which is an array of `t_symbol*`, > but not the `t_symbol*` elements themselves. > > --- > > Side note: since symbols are unique and persistent, they can be compared *by > address*. In other words, two symbols are equal if they have the same > address. This is different from ordinary C-strings which may reside at > different memory locations and thus need to be compared with `strcmp()` (or > equivalent functions). > > Christof > > On 22.02.2024 10:19, Alexandros Drymonitis wrote: >> I have a data structure with a symbol and an array of symbols that store >> array names defined as: >> >> ``` >> t_symbol **x_weights_arrays; >> t_symbol *x_biases_array; >> ``` >> >> When I'm done with them, I want to free the memory, but calling >> free(x_biases_array) doesn't seem to work, and once called, as soon as I try >> to do something else in Pd (like unlock the patch and choose an object), Pd >> crashes. >> >> I have narrowed down the error to freeing these symbols, and I'm sure the >> crash is not caused by something else. I scanned m_pd.h to see if there is a >> function to free t_symbol memory, but didn't seem to find anything. This >> might be something obvious for C-savvy people, but I'm not one, so any >> advice is welcome. >> >> >> >> >> _______________________________________________ >> Pd-dev mailing list >> [email protected] >> https://lists.puredata.info/listinfo/pd-dev > > > > _______________________________________________ > Pd-dev mailing list > [email protected] > https://lists.puredata.info/listinfo/pd-dev _______________________________________________ Pd-dev mailing list [email protected] https://lists.puredata.info/listinfo/pd-dev
