pg_config shows 9.4 instead of 9.3

Question

I am using Postgres 9.3, however my pg_config points at 9.4, preventing me from building extensions (pgTap).

$ sudo aptitude search postgresql | grep ^i
i   postgresql-9.3                  - object-relational SQL database,
version 9.
i   postgresql-client-9.3           - front-end programs for PostgreSQL 9.3

i A postgresql-client-common        - manager for multiple PostgreSQL client
ver
i A postgresql-common               - PostgreSQL database-cluster manager

i   postgresql-contrib-9.3          - additional facilities for PostgreSQL

As you can see above I have 9.3 installed

$ pg_config
BINDIR = /usr/lib/postgresql/9.4/bin
DOCDIR = /usr/share/doc/postgresql-doc-9.4
HTMLDIR = /usr/share/doc/postgresql-doc-9.4
INCLUDEDIR = /usr/include/postgresql
PKGINCLUDEDIR = /usr/include/postgresql
INCLUDEDIR-SERVER = /usr/include/postgresql/9.4/server
LIBDIR = /usr/lib/x86_64-linux-gnu
PKGLIBDIR = /usr/lib/postgresql/9.4/lib
LOCALEDIR = /usr/share/locale
MANDIR = /usr/share/postgresql/9.4/man
SHAREDIR = /usr/share/postgresql/9.4
SYSCONFDIR = /etc/postgresql-common
PGXS = /usr/lib/postgresql/9.4/lib/pgxs/src/makefiles/pgxs.mk
CONFIGURE = '--with-tcl' '--with-perl' '--with-python' '--with-pam'
'--with-openssl' '--with-libxml' '--with-libxslt'
'--with-tclconfig=/usr/lib/tcl8.5' '--with-includes=/usr/include/tcl8.5'
'PYTHON=/usr/bin/python' '--mandir=/usr/share/postgresql/9.4/man'
'--docdir=/usr/share/doc/postgresql-doc-9.4'
'--sysconfdir=/etc/postgresql-common' '--datarootdir=/usr/share/'
'--datadir=/usr/share/postgresql/9.4' '--bindir=/usr/lib/postgresql/9.4/bin'
'--libdir=/usr/lib/x86_64-linux-gnu/' '--libexecdir=/usr/lib/postgresql/'
'--includedir=/usr/include/postgresql/' '--enable-nls'
'--enable-integer-datetimes' '--enable-thread-safety' '--enable-debug'
'--disable-rpath' '--with-uuid=e2fs' '--with-gnu-ld' '--with-pgport=5432'
'--with-system-tzdata=/usr/share/zoneinfo' 'CFLAGS=-g -O2 -fstack-protector
--param=ssp-buffer-size=4 -Wformat -Wformat-security -Werror=format-security
-I/usr/include/mit-krb5 -fPIC -pie -DLINUX_OOM_SCORE_ADJ=0
-fno-omit-frame-pointer' 'LDFLAGS=-Wl,-Bsymbolic-functions -Wl,-z,relro
-Wl,-z,now -Wl,--as-needed -L/usr/lib/mit-krb5
-L/usr/lib/x86_64-linux-gnu/mit-krb5' '--with-krb5' '--with-gssapi'
'--with-ldap' 'CPPFLAGS=-D_FORTIFY_SOURCE=2'
CC = gcc
CPPFLAGS = -D_FORTIFY_SOURCE=2 -D_GNU_SOURCE -I/usr/include/libxml2
-I/usr/include/tcl8.5
CFLAGS = -Wall -Wmissing-prototypes -Wpointer-arith
-Wdeclaration-after-statement -Wendif-labels -Wmissing-format-attribute
-Wformat-security -fno-strict-aliasing -fwrapv -fexcess-precision=standard
-g -g -O2 -fstack-protector --param=ssp-buffer-size=4 -Wformat
-Wformat-security -Werror=format-security -I/usr/include/mit-krb5 -fPIC -pie
-DLINUX_OOM_SCORE_ADJ=0 -fno-omit-frame-pointer
CFLAGS_SL = -fpic
LDFLAGS = -L../../../src/common -Wl,-Bsymbolic-functions -Wl,-z,relro
-Wl,-z,now -Wl,--as-needed -L/usr/lib/mit-krb5
-L/usr/lib/x86_64-linux-gnu/mit-krb5 -L/usr/lib/x86_64-linux-gnu
-Wl,--as-needed
LDFLAGS_EX =
LDFLAGS_SL =
LIBS = -lpgcommon -lpgport -lxslt -lxml2 -lpam -lssl -lcrypto -lgssapi_krb5
-lz -ledit -lrt -lcrypt -ldl -lm
VERSION = PostgreSQL 9.4.1

Running ls against any of the /postgresql locations from pg_config (e.g. /usr/lib/postgresql) only return 9.3.

Running which pg_config results in: /usr/bin/pg_config

Looking into /usr/bin/pg_config (with vi), the following are the contents:

PGBINROOT="/usr/lib/postgresql/"
LATEST_SERVER_DEV=`ls $PGBINROOT*/bin/pg_config 2>/dev/null|tail -n1`

if [ -n "$LATEST_SERVER_DEV" ]; then
    exec "$LATEST_SERVER_DEV" "$@"
else
    if [ -x /usr/bin/pg_config.libpq-dev ]; then
        exec /usr/bin/pg_config.libpq-dev "$@"
  ...
  ...
  ...

Now looking in /usr/lib/postgresql/9.3/bin does NOT produce a pg_config file.

using apt-get purge postgresql-9.3 followed by apt-get install postgresql-9.3 does NOT fix the problem.

The closest I have found to an answer is this:

https://bugs.launchpad.net/ubuntu/+source/postgresql-common/+bug/789622

I have taken both steps advocated (upgrading libpq5 and libpq-dev) to no effect.

Any insights into how this could have happened, and how to fix it (or at least work around it?) I would settle for the ability to manually repoint pg_config (though an actual explanation and fix would be better). Is there just a way for me to instantiate a pg_config file in the /usr/lib/postgresql/9.3 directory?

Answer 1

This got fixed for me by running:

sudo apt-get install postgresql-server-dev-9.3

I still don't really know how I got into that state though.

Answer 2

I got into the same problem by running :

apt-get install postgresql-server-dev-all

on a pg9.4 instance, which installed the package for versions 9.1, 9.2, 9.3, 9.4 and 9.5.

It turns out that this script :

/usr/bin/pg_config

finds the latest version and runs it :

#!/bin/sh

# If postgresql-server-dev-* is installed, call pg_config from the latest
# available one. Otherwise fall back to libpq-dev's version.
#
# (C) 2011 Martin Pitt <[email protected]>
#
#  This program is free software; you can redistribute it and/or modify
#  it under the terms of the GNU General Public License as published by
#  the Free Software Foundation; either version 2 of the License, or
#  (at your option) any later version.
#
#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
set -e
PGBINROOT="/usr/lib/postgresql/"
LATEST_SERVER_DEV=\`ls $PGBINROOT*/bin/pg_config 2>/dev/null|tail -n1\`

if [ -n "$LATEST_SERVER_DEV" ]; then
    exec "$LATEST_SERVER_DEV" "$@"
else
    if [ -x /usr/bin/pg_config.libpq-dev ]; then
    exec /usr/bin/pg_config.libpq-dev "$@"
    else
    echo "You need to install postgresql-server-dev-X.Y for building a server-side extension or libpq-dev for building a client-side application." >&2
    exit 1
    fi
fi

The solution was to remove the directory : /usr/lib/postgresql/9.5

Answer 3

Ubuntu designs its Postgres packages so that most commands will take a PGCLUSTER envvar with a value like 9.5/main to let you control which version/cluster the command should use. Sadly pg_config doesn't! But /usr/bin/pg_config is just a bash wrapper, so I added a few lines like so:

set -e
PGBINROOT="/usr/lib/postgresql/"
#redhat# PGBINROOT="/usr/pgsql-"

# MY CHANGES START HERE
if [ -n "$PGCLUSTER" ]; then
  exec "$PGBINROOT/$PGCLUSTER/bin/pg_config" "$@"
fi
# MY CHANGES END HERE

LATEST_SERVER_DEV=`ls $PGBINROOT*/bin/pg_config 2>/dev/null|tail -n1`

if [ -n "$LATEST_SERVER_DEV" ]; then
    exec "$LATEST_SERVER_DEV" "$@"
else
    if [ -x /usr/bin/pg_config.libpq-dev ]; then
  exec /usr/bin/pg_config.libpq-dev "$@"
    else
  echo "You need to install postgresql-server-dev-X.Y for building a server-side extension or libpq-dev for building a client-side application." >&2
  exit 1
    fi
fi

That doesn't support the cluster part of the usual PGCLUSTER string, but you can still say PGCLUSTER=9.3 make e.g. This helps me when I'm building postgres extensions for a version I have installed that isn't the most recent.

I guess it might be safer to use a different name for my variable here, but it hasn't caused me problems so far. :-)