Re: [gentoo-user] Using date/time variables in cronjobs?

[Alan McKinnon <alan.mckinnon@gmail.com>]

On 05/05/2013 18:56, Tanstaafl wrote:
> Ok, another little thing...
> 
> Is there a simple way to use date/time variables in cronjobs? Or do I
> need to use a bash script for this? I prefer simple, and just using the
> variables directly in the cron command would be easier if it works, so
> figured I'd ask first...
> 
> I'm trying to schedule a dump of my databases like so:
> 
> pg_dumpall --username=username -o -f
> /home/user/mypg_backups/hourly/\%y/\%m/\%d/\%t.sql.gz
> 
> But trying to run this command fails with:
> 
> pg_dumpall: could not open the output file
> "/home/user/mypg_backups/hourly/%y/%m/%d/%t.sql.gz": No such file or
> directory
> 
> Tried escaping the variables and not, same error...


What creates those variables %y etc? They don't "just exist", something
sets them. Check that that thing sets them correctly.

But I'll bet the directory /home/user/mypg_backups/hourly/\%y/\%m/\%d/
doesn't exist. pg_dumpall won;t create it, that's your job.

So now you need a test that the directory exists, mkdir -p it if not,
and only then write the output file. Which is far easier done in a
wrapper script than in a one-liner, if only for the fact that you have
indented text.

Sometimes, making things simpler makes your life harder. This looks like
such a case.


-- 
Alan McKinnon
alan.mckinnon@gmail.com