Message-ID: <502EA0D0.10004@gmx.net>
Date: Fri, 17 Aug 2012 15:51:44 -0400
From: Peter Eisentraut <peter_e@gmx.net>
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To: Bruce Momjian <bruce@momjian.us>
CC: Josh Kupershmidt <schmiddy@gmail.com>, Greg Smith <greg@2ndquadrant.com>,
	Euler Taveira de Oliveira <euler@timbira.com>, pgsql-docs@postgresql.org
Subject: Re: somewhat wrong archive_command example
References: <1316524671.9044.12.camel@fsopti579.F-Secure.com>
	<4E794FB5.80400@2ndQuadrant.com>
	<1316613536.14119.6.camel@fsopti579.F-Secure.com>
	<4E7A6D0D.4060106@2ndQuadrant.com> <4E7A887F.8010908@timbira.com>
	<CAK3UJRHChOcGQ0kzu01wZX6PB9pScHSzg1X+hThdR7QXWoe1yw@mail.gmail.com>
	<20120816011347.GF8353@momjian.us>
In-Reply-To: <20120816011347.GF8353@momjian.us>
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On 8/15/12 9:13 PM, Bruce Momjian wrote:
>> Few more suggestions/nitpicks:
>>   1.) IMO it's more logical to put the test for whether the $ARCHIVE
>> directory exists before the test whether ${ARCHIVE}/${FILE} exists.
>>   2.) I think the error code reporting here is not sound:
>>
>> cp ${FULLPATH} ${ARCHIVE}/${FILE}
>> if [ $? -ne 0 ] ; then
>>    echo $0 Archive copy of ${FILE} failed with error $? >&2
>>
>> at least on my OS X machine, that echo produces a message like
>> "./local_backup_script.sh Archive copy of failed with error 0", I
>> guess since $? gets reset to 0 after that if-statement. You can use a
>> temporary variable like $ERRCODE=$? to get around this.
>
> I have made all the suggestions posted and would like to add the
> attached script to our documentation as a simple example.

Btw., is anyone else concerned about using plain cp for this?  If the cp 
fails half-way, it leaves a partial file around, but subsequent file 
existence checks will find the file OK and skip it.

I have occasionally used some combination of mktemp + cp + mv, which 
seems to work around this problem.