Examples of using PQexecParams

I was looking for examples of using PQexecParams but all I found was
this: http://sepp.oetiker.ch/postgresql-8.2.3-ds/libpq-example.html

/* Convert integer value "2" to network byte order */
binaryIntVal = htonl((uint32_t) 2);
/* Set up parameter arrays for PQexecParams */
paramValues[0] = (char *) &binaryIntVal;
paramLengths[0] = sizeof(binaryIntVal);
paramFormats[0] = 1; /* binary */
...
seems a bit convoluted.

In particular I was looking for an example of setting up a string
parameter for PQexecParams, assuming that is possible.