Re: [igraph] Segmentation fault constructing graph when using igraph_attribute_table_t

[Tamas Nepusz]

Hi Natalia,

The "attribute table" is a set of handler functions that are called  
whenever something related to the graph attributes happen. (So it's  
not a table that stores graph attributes directly). The table is empty  
per default (no attribute handling is enabled). If you want to enable  
attribute handling in C, you have to attach the (pretty experimental)  
C attribute handler functions to the attribute table as follows:

igraph_i_set_attribute_handler(&igraph_cattribute_table);

igraph_cattribute_table is a predefined table that refer to the  
attribute handler routines implemented in C. (When igraph runs inside  
Python or R, the attribute table is replaced by the respective Python  
or R attribute handler routines).

> igraph_attribute_table_t table;
> igraph_i_set_attribute_table(&table);
This doesn't work because the contents of the table that you created  
are undefined, and igraph will call a random memory address as a  
function whenever you create a graph.

--
Tamas