sS apertium_en2es(S s) {
  File inFile = createTempFile(), outFile = createTempFile();
  temp tempDeleteFile(inFile);
  temp tempDeleteFile(outFile);
  saveTextFile(inFile, s);
  backtick_verbose("apertium -u eng-spa " + platformQuote(inFile) + " " + platformQuote(outFile));
  ret loadTextFile(outFile);
}