Linking attributes to a struct within an object

https://github.com/CICM/HoaLibrary/blob/master/Max6/MaxAmbisonic.cpp

Yes, you are right ! It works but I don’t know where is my attribute… In fact, it seems that m_order isn’t the variable of my attribute. I used to use object_attr_get so I didn’t realize the problem. OBJ_ATTR_LONG (&m_order) isn’t the solution, I’ll have to investigate…

Thanks for this feedback !

Hi there!

I am a (very) newbie in MaxMSP and I already have to create my own external. My problem is very close to yours (I guess): I want to read 5 text files and get access to each one of them in my object. To do this I have created a struct to fill in the data. Each time a message “read” incomes I create a new structure that I fill with the data from the text file, my problem is how to get access to those 5 structures in the rest of my program?
Should I add some attributes to my object (but add then 5 struct attributes?)

the structures:
typedef struct _recognition {
t_object p_ob;
void *p_outlet;
} t_recognition;

typedef struct _model {
char id;
double A[NBSTATE][NBSTATE];
double cov[NBSTATE*NBFEAT][NBFEAT];
double mu[NBSTATE][NBFEAT];
} t_model;

In the main
c = class_new(“recognition”, (method)recognition_new, (method)NULL, sizeof(t_recognition), 0L, A_DEFLONG, 0);
class_addmethod(c, (method)myobject_read, “read”, A_DEFSYM, 0);

the functions:

void myobject_read(t_object *x, t_symbol *s)
{
defer(x, (method)myobject_doread, s, 0, NULL);
}

void myobject_doread(t_object *x, t_symbol *s)
{
// ….. find the filename etc
myobject_openfile(x, filename, path);
}

t_model *myobject_openfile(t_object *x, char *filename, short path)
{
t_filehandle fh;
char *buffer;
t_ptr_size size;
int count=0;

t_model *mod = (t_model *)malloc(sizeof(t_model));

if (path_opensysfile(filename, path, &fh, READ_PERM)) {
object_error(x, “error opening %s”, filename);
return mod;

}

mod->id=filename[6];

// allocate memory block that is the size of the file
sysfile_geteof(fh, &size);
buffer = sysmem_newptr(size);
// read in the file
sysfile_read(fh, &size, buffer);
sysfile_close(fh);

// fill the structure mod

sysmem_freeptr(buffer); // must free allocated memory

return mod;
}

So each time there is a “read” message, I create and fill a new structure t_model *mod and send back a pointer to this structure but where can I access to it? And how to be sure I create a new structure for each read and not writing over?

Thank you to answer me so quickly!
I need indeed to access my five t_model in other methods of my external. I think you are right saying I need an array of pointers. But how I can instantiate them without a malloc? I have found the function system_newptr but it looks to work only with pointers of type char and I need pointers of type t_model.
I have tried this:
in my object structure:
t_model *ptr_model[5];

in the method to instantiate the object (my object_new)
for(int i=0; iptr_model[i]=sysmem_newptr(sizeof(t_model));
}
and I get a warning “Incompatible pointer type assigning to ‘t_model *’ from ‘t_ptr’”

Is there any other function to do so?

I am sure that my problem is about knowing generic techniques for Max/MSP objects and I have already make smaller objects from my own and read the examples in MaxSDK in order to understand the basics but it looks not to be enough.