The curly library essentially implements popen() by piping the output of
curl to a temporary file via system(). The file is then opened and
the results are passed back to the calling program. This approach has the
advantage that the developer can view the response outside of the program and
known responses can be injected during unit test.
References
- https://en.wikipedia.org/wiki/Arbitrage
- https://en.wikipedia.org/wiki/Law_of_one_price
- https://en.wikipedia.org/wiki/Men%27s_underwear_index
- https://medium.com/@petersellis/how-to-arbitrage-bitcoin-fc0098ac0511
- https://bitcoincharts.com/markets/currency/USD.html