Re: ftell mismatch with expected position

Please refrain from top-posting.

On 2 November 2015 at 10:48, Eelke Klein <eelke(at)bolt(dot)nl> wrote:
> Normally we call this from within our windows program where a lot of code is
> involved for setting up the environment, and creating the pipes and
> redirecting stdout, stderr and stdin. However I believe it is the same
> problem that can be caused with the following commandline in cmd.exe but you
> will need to have Coreutils for windows installed to get the cat command.
>
> pg_dump.exe -U postgres --format=c mydb | cat > backupfile

Do you also get the warning if you split those commands up, and if so,
in which one?

pg_dump.exe -U postgres --format=c mydb > backupfile
cat backupfile > someotherfile

> The size of the backup doesn't matter. As long as there is atleast one table
> in the database the warning occurs. When I use --verbose it looks like I get
> one warning for every table in the database while it is dumping the data in
> the tables.
>
> Eelke Klein
>
>
> 2015-10-30 14:53 GMT+01:00 Adrian Klaver <adrian(dot)klaver(at)aklaver(dot)com>:
>>
>> On 10/29/2015 02:51 AM, Eelke Klein wrote:
>>>
>>> I am getting the following warning when our program runs pg_dump.exe and
>>> the output is in custom format and send to standard out which is
>>> connected to a pipe (Windows platform).
>>>
>>> pg_dump: [custom archiver] WARNING: ftell mismatch with expected
>>> position -- ftell used
>>
>>
>> Can you show us the exact command, with arguments, that you are using?
>>
>> Also what is the size of the dump file you are creating?
>>
>>
>>>
>>> The output of pg_dump is received by another process that copies it (and
>>> some other data) into a zip file. When I extract the db backup from the
>>> zip the backup is fine and I can restore it.
>>>
>>> I have both tried the pg_dump.exe from the 9.5 alpha and a stable 9.4
>>> both generate this warning.
>>> When I change the format to plain the warning goes away.
>>> When I call pg_dump from the commandline and let it send to standard out
>>> and redirect it to a file the warning does not occur but it does occur
>>> when I redirect to nul.
>>>
>>> Is there a way to prevent this warning? I would think pg_dump shouldn't
>>> call ftell on a pipe.
>>>
>>> Regards, Eelke
>>
>>
>>
>> --
>> Adrian Klaver
>> adrian(dot)klaver(at)aklaver(dot)com
>
>

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