/* Check if given line is a shell command. */
static int is_shell_command(const char *line_p)
/* Check if given line is a shell command. */
static int is_shell_command(const char *line_p)
{
    if (*line_p == '/') {
        line_p++;
    }
    return (shell_command_compare(line_p, FSTR("logout"), 6)
            || shell_command_compare(line_p, FSTR("history"), 7)
            || shell_command_compare(line_p, FSTR("help"), 4));
}