Re: psql and named pipes

From: Aidan Van Dyk <aidan(at)highrise(dot)ca>
To: Alvaro Herrera <alvherre(at)commandprompt(dot)com>
Cc: Pg Hackers <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: psql and named pipes
Date: 2008-03-27 17:05:17
Views: Raw Message | Whole Thread | Download mbox | Resend email
Lists: pgsql-hackers

* Alvaro Herrera <alvherre(at)commandprompt(dot)com> [080327 12:58]:
> I was under the impression that I could start a "psql -f pipe" and then
> feed it commands through the pipe using echo, and expect it to hang from
> one command to the next. Of course, this doesn't work -- my guess is
> that echo sends an EOF after the line I send, so psql sees the EOF in
> the pipe and terminates.
> Does anyone have an idea how to go about this? I was expecting to be
> able to drive two psql sessions in parallel in a shell script -- sort of
> poor man's concurrent psql :-(

I've had to use:
while (true); do cat pipe; done | psql

The trick is that pipes "EOF"s everytime the cleint closes it. (Not
strictly true, but it appears that way to basic read()ers).

You can see a more compilcated setup I use to echo commands to a pipe
going to a psql here:

Aidan Van Dyk Create like a god,
aidan(at)highrise(dot)ca command like a king, work like a slave.

In response to


Browse pgsql-hackers by date

  From Date Subject
Next Message Gregory Stark 2008-03-27 17:30:14 Re: Windows shared_buffers limitations
Previous Message Alvaro Herrera 2008-03-27 16:56:39 psql and named pipes