Re: pg_ctl

Tatsuo Ishii <t-ishii(at)sra(dot)co(dot)jp> writes:
> Here is the first draft for the spec of postmaster starting/stopping
> tool. I have named it as "pg_ctl."
> o pg_ctl [-w] start
> start up postmaster.

How will pg_ctl know what to start --- where do the database directory,
port number, and path (to locate the postmaster executable) come from?

> Options for postmaster should be placed in
> $PGDATA/postmaster.conf.

Port number could reasonably be kept there, but I'm less sure about
path, and for sure there must be another way for pg_ctl to find PGDATA
in the first place...

> It would be nice if it could report,
> for example, the number of backends running (and their pids) etc. For
> this purpose I propose followings:

> (1) Add another protocol STATUS_REQUEST_CODE to libpq/pqcomm.h.

> (2) Add code to process the protocol in
> postmaster/postmaster.c:readStartupPacket().

Security issues may be a factor here. Do you want just anyone anywhere
on the net to be able to extract the postmaster status? If not, how
shall we restrict it?

regards, tom lane