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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Jeroen Vermeulen <jtvjtv@gmail.com>
cc: pgsql-interfaces@postgresql.org
Subject: Re: libpq: make PGresult* "const" in PQcmdStatus()/PQcmdTuples()?
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Jeroen Vermeulen <jtvjtv@gmail.com> writes:
> Any objections to changing these two libpq functions' PGresult* parameters
> to be const?

> So "char * PQcmdStatus(PGresult *)" would become "char *PQcmdStatus(const
> PGresult *)", and "char *PQcmdTuples(PGresult *)" would become "char
> *PQcmdTuples(const PGresult *)".

Both of those return pointers to res->cmdStatus, so it would not make
any sense to const-ify the argument unless you also const-ify the
result; which would cause compiler warnings for users.  I'm pretty
sure we've explicitly rejected making this change for that reason.

			regards, tom lane