X-Original-To: pgsql-interfaces-postgresql.org@localhost.postgresql.org Received: from localhost (unknown [200.46.204.144]) by svr1.postgresql.org (Postfix) with ESMTP id 8E0F63A5F93 for ; Thu, 13 Jan 2005 19:50:08 +0000 (GMT) Received: from svr1.postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id 95672-05 for ; Thu, 13 Jan 2005 19:49:57 +0000 (GMT) Received: from sss.pgh.pa.us (sss.pgh.pa.us [66.207.139.130]) by svr1.postgresql.org (Postfix) with ESMTP id D45443A5E63 for ; Thu, 13 Jan 2005 19:49:58 +0000 (GMT) Received: from sss2.sss.pgh.pa.us (tgl@localhost [127.0.0.1]) by sss.pgh.pa.us (8.13.1/8.13.1) with ESMTP id j0DJnun6012840; Thu, 13 Jan 2005 14:49:56 -0500 (EST) To: puetz@mpipsykl.mpg.de Cc: pgsql-interfaces@postgresql.org Subject: Re: How to detect NULL in VarChar (C function) In-reply-to: <41E6A794.6020701@mpipsykl.mpg.de> References: <41E6A794.6020701@mpipsykl.mpg.de> Comments: In-reply-to =?ISO-8859-1?Q?Benno_P=FCtz?= message dated "Thu, 13 Jan 2005 17:53:40 +0100" Date: Thu, 13 Jan 2005 14:49:56 -0500 Message-ID: <12839.1105645796@sss.pgh.pa.us> From: Tom Lane X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0.004 tagged_above=0 required=5 tests=AWL X-Spam-Level: X-Archive-Number: 200501/5 X-Sequence-Number: 5231 =?ISO-8859-1?Q?Benno_P=FCtz?= writes: > I have not been able to find a description of how to detect NULL values > in VarChar variables passed to C-functions to catch those cases. Use PG_ARGISNULL(). See 33.7.4. Calling Conventions Version 1 for C-Language Functions at http://www.postgresql.org/docs/7.4/static/xfunc-c.html regards, tom lane