You may have seen the message system...

not for the faint-of-heart, but very instructive: A 3-dimensional, dynamically allocated array.

The dimensions are state (type , source , severity). We allocate the array dynamically in the class constructor because we don’t want to hard-wire the respective numbers.

class filter_msg_buffer : public msg_buffer {

streambuf * original_streambuf;

int ***state;

// stuff deleted

// allocate new memory for the matrix

state = new int **[msg_type_max];

for (i=0; i< msg_type_max; i++)

{

state[i] = new int* [msg_source_max];

for ( j =0; j<msg_source_max; j++)

state[i][j] = new int [msg_sev_max];

}

for (i=0; i < msg_type_max; i++)

for (j=0; j < msg_source_max ; j++)

for (k=0; k < msg_sev_max ; k++)

state[i][j][k] = ON;

}

please convince yourself that we end up with an appropriately-sized array, and that we free the memory again correctly.

// free memory from the matrix

int i,j;

for (i=0; i< msg_type_max; i++)

{

for ( j =0; j<msg_source_max; j++)

delete [] state[i][j];

delete [] state[i] ;

}

delete [] state;

}

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