The World Bank suggests 3 policy options during currency wars: a country could 

1) Use its own monetary policy. But then the WB observes "appropriate monetary policy in many developing economies at present would likely be to tighten, which will however attract even more capital inflows and further appreciate exchange rates."  

2) Fixed exchange rates, which would require the country to "ceding control of monetary policy as an independent policy instrument." This would imply "importing loose U.S. monetary policy to stimulate excessive domestic money growth, inflation in the goods market, and speculative bubbles in asset markets. In this case, adjustment will occur through high inflation (with its attendant efficiency and equity costs) and appreciation of the real exchange rate." 

3) "combine an independent monetary policy with a fixed exchange rate by closing the capital account through capital controls." This will lead in inefficient allocation of capital and a destortion in the longer maturities.  Argentina seems to have used the latter path – but life without captial flows is not all that easy (see link). As the Argentiniean "government’s economic model is based on aggressive monetary expansion to support swelling budget deficits, currency and capital controls" the MF model tells us that the duration of these policies is limited by Argentina's foreign currency reserves.