libq API question

Hi, ALL,

In the docs I see the following:

[quote]

PGresult *PQexecParams(PGconn *conn,
const char *command,
int nParams,
const Oid *paramTypes,
const char * const *paramValues,
const int *paramLengths,
const int *paramFormats,
int resultFormat);
[/quote]

Is there a reason why the parameters are int and not unsigned int?

There is no way the length can be negative...

Is it for backward compatibility?

Thank you.