int c_shquote_append_char(char **outp,
                          size_t *n_outp,
                          char in) {
        return c_shquote_append_str(outp, n_outp, &in, 1);
}
int c_shquote_append_char(char **outp,
                          size_t *n_outp,
                          char in) {
        return c_shquote_append_str(outp, n_outp, &in, 1);
}