Re: archive_commnad parameter question

On 2021-04-19 21:09:13 +0000, Allie Crawford wrote:
> I am new in PostgreSQL and I am trying to understand what the “test” word is
> representing in the archive_command configuration that the PostgreSQL
> documentation is showing as the format on how to set up this parameter
>
> archive_command = 'test ! -f /mnt/server/archivedir/%f && cp %p /mnt/server/
> archivedir/%f'  # Unix
>
> Does anybody know what is “test” representing in this parameter configuration?

"test" is a unix command for testing stuff (as the name implies).
"test -f" in particular tests whether the argument exists and is a
regular file) and the "!" inverts the result.

So the whole line checks that the target *doesn't* already exist before
attempting to copy over it.

        hp

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