$$\lim_{x \to \infty} \operatorname{sign}{\left(\sin{\left(\frac{\pi}{x} \right)} \right)} = 0$$
$$\lim_{x \to 0^-} \operatorname{sign}{\left(\sin{\left(\frac{\pi}{x} \right)} \right)} = \operatorname{sign}{\left(\left\langle -1, 1\right\rangle \right)}$$
More at x→0 from the left$$\lim_{x \to 0^+} \operatorname{sign}{\left(\sin{\left(\frac{\pi}{x} \right)} \right)} = \operatorname{sign}{\left(\left\langle -1, 1\right\rangle \right)}$$
More at x→0 from the right$$\lim_{x \to 1^-} \operatorname{sign}{\left(\sin{\left(\frac{\pi}{x} \right)} \right)}$$
More at x→1 from the left$$\lim_{x \to 1^+} \operatorname{sign}{\left(\sin{\left(\frac{\pi}{x} \right)} \right)}$$
More at x→1 from the right$$\lim_{x \to -\infty} \operatorname{sign}{\left(\sin{\left(\frac{\pi}{x} \right)} \right)} = 0$$
More at x→-oo