Re: pg11+: pg_ls_*dir LIMIT 1: temporary files .. not closed atend-of-transaction - Mailing list pgsql-hackers

From Fabien COELHO
Subject Re: pg11+: pg_ls_*dir LIMIT 1: temporary files .. not closed atend-of-transaction
Date
Msg-id alpine.DEB.2.21.2003300704430.16227@pseudo
Whole thread Raw
In response to Re: pg11+: pg_ls_*dir LIMIT 1: temporary files .. not closed atend-of-transaction  (Justin Pryzby <pryzby@telsasoft.com>)
Responses Re: pg11+: pg_ls_*dir LIMIT 1: temporary files .. not closed at end-of-transaction  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
Hello Justin,

>> Well, the following comment says "ignore anything but regular files",
>> so I'm supposing that that is the behavior that we actually want here
>> and failed to implement correctly.  There might be scope for
>> additional directory-reading functions, but I'd think you'd want
>> more information (such as the file type) returned from anything
>> that doesn't act this way.
>
> Maybe pg_stat_file() deserves similar attention ?  Right now, it'll fail on a
> broken link.  If we changed it to lstat(), then it'd work, but it'd also show
> metadata for the *link* rather than its target.

Yep. I think this traditional answer is the rational answer.

As I wrote about an earlier version of the patch, ISTM that instead of 
reinventing, extending, adapting various ls variants (with/without 
metadata, which show only files, which shows target of links, which shows 
directory, etc.) we would just need *one* postgres "ls" implementation 
which would be like "ls -la arg" (returns file type, dates), and then 
everything else is a wrapper around that with appropriate filtering that 
can be done at the SQL level, like you started with recurse.

It would reduce the amount of C code and I find the SQL-level approach 
quite elegant.

-- 
Fabien.



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