/*
 * call-seq: StringIO.open(string=""[, mode]) {|strio| ...}
 *
 * Equivalent to StringIO.new except that when it is called with a block, it
 * yields with the new instance and closes it, and returns the result which
 * returned from the block.
 */
static VALUE
strio_s_open(argc, argv, klass)
    int argc;
    VALUE *argv;
    VALUE klass;
{
    VALUE obj = rb_class_new_instance(argc, argv, klass);
    if (!rb_block_given_p()) return obj;
    return rb_ensure(rb_yield, obj, strio_finalize, obj);
}