snprintf()

From: Kate F <kate(at)cats(dot)meow(dot)at>
To: pgsql-hackers(at)postgresql(dot)org
Subject: snprintf()
Date: 2007-02-03 03:40:18
Message-ID: 20070203034018.GH390@cats.meow.at
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

Hello,

I've been implementing a type I needed, and happened to be using
snprintf(), since I have C99 available.

ereport(NOTICE,
(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
errmsg("%d", snprintf(NULL, 0, "abc"))));

For me, this reports "0". I beieve it should report 3. My system's
snprintf() returns 3. I'm using NetBSD. By including postgres.h and
fmgr.h, does PostgreSQL replace my system's snprintf() prototype with
its own implementation's?

Placing stdio.h above those includes appears to have no effect.

For reference, the relevant part of C99:

7.19.6.5 2 If n is zero, nothing is written, and s may be a null
pointer.

7.19.6.5 3 The snprintf function returns the number of characters
that would have been written had n been sufficiently large, not
counting the terminating null character, or a neg ative value if an
encoding error occurred.

Regards,

--
Kate

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Tom Lane 2007-02-03 03:52:28 Re: snprintf()
Previous Message Jeremy Drake 2007-02-03 03:01:33 Re: [HACKERS] writing new regexp functions