Postgres 9.4 0 undefined symbol - PQhostaddr

Question

I have installed postgres9.4 on Ubuntu
I used to be able to run psql just fine.

symbol lookup error: /usr/lib/postgressql/9.4/bin/psql: undefined symbol: PQhostaddr

As per Craig's comment I did a little digging.

I confirmed using ldd that PQhostaddr is the only exception.

I also tried this:

$ sudo ldconfig -v | grep libpq
/sbin/ldconfig.real: Path /lib/x86_64-linux-gnu' given more than once /sbin/ldconfig.real: Path/usr/lib/x86_64-linux-gnu' given more than once
/sbin/ldconfig.real: /lib/x86_64-linux-gnu/ld-2.19.so is the dynamic linker, ignoring

libpq.so.5 -> libpq.so.5.7

I can however only see the directories in each place once. (not repeated)
I also can't find libpq

So generally not doing amazingly with this. I would have assumed there was a method of updating libpq.so.5.7

Am I barking up the wrong tree? (Or just barking mad)

psql has nothing to do with psycopg2. Please give us the exact error psql gives you. We can't figure out what's happening with a just a phrase like "I can't seem to get it to run anymore" — Jérôme Radix
The libpq being found on the library path (/etc/ld.so.conf and LD_LIBRARY_PATH) is older than the version in 9.4. Use ldd /usr/lib/postgressql/9.4/bin/psql to find out which version is being linked to. — Craig Ringer
Thanks Craig, that makes sense. I have libpq.so.5 being linked to. I looked in ld.so.conf, which includes ld.so.conf.d which is blank (that doesn't seem good). Also echo $LD_LIBRARY_PATH is also blank (although it is defined) - also not good. Thanks for bearing with me — reabow
did you ever find a solution? I am having the same exact issue. — Jared Mackey

Jared Mackey Jared Mackey · Accepted Answer · 2015-03-02T14:22:49

I had the same issue but I was able to resolve it by completely removing postgresql with these commands.

apt-get --purge remove postgresql\*
 rm -r /etc/postgresql/
 rm -r /etc/postgresql-common/
 rm -r /var/lib/postgresql/
 userdel -r postgres
 groupdel postgres

Then reinstalling postgresql.

Postgres 9.4 0 undefined symbol - PQhostaddr

2 Answers