Horton

Re: pipe_read_line for reading arbitrary strings

Alvaro Herrera <alvherre@alvh.no-ip.org>

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From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Daniel Gustafsson <daniel@yesql.se>
Cc: Peter Eisentraut <peter@eisentraut.org>, Postgres hackers <pgsql-hackers@lists.postgresql.org>
Date: 2024-03-06T10:46:29Z
Lists: pgsql-hackers 
On 2024-Mar-06, Daniel Gustafsson wrote:

> Good catch, that's an incorrect copy/paste, it should use ERRCODE_NO_DATA.  I'm
> not convinced that a function to read from a pipe should consider not reading
> anything successful by default, output is sort expected here.  We could add a
> flag parameter to use for signalling that no data is fine though as per the
> attached (as of yet untested) diff?

I think adding dead code is not a great plan, particularly if it's hairy
enough that we need to very carefully dissect what happens in error
cases.  IMO if and when somebody has a need for an empty return string
being acceptable, they can add it then.

-- 
Álvaro Herrera               48°01'N 7°57'E  —  https://www.EnterpriseDB.com/

Commits

  1. Fix errorhandling for reading from a pipe

  2. Refactor pipe_read_line to return the full line

  3. Add -c/--restore-target-wal to pg_rewind

  4. Here is a patch that fixes the pipes used in find_other_exec() when