static bool checkCurl() {
	const char nul[] = R_SYS_DEVNULL;
	if (r_sys_cmdf ("curl --version > %s", nul) != 0) {
		return false;
	}
	return true;
}
The software constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.