The first thing that a host application has to do, is create a virtual machine. The host application can create any number of virtual machines through the function sq_open().
Every single VM has to be released with the function sq_close() when it is not needed anymore.
int main(int argc, char* argv[])
{
HSQUIRRELVM v;
v = sq_open(1024); //creates a VM with initial stack size 1024
//do some stuff with squirrel here
sq_close(v);
}