ran vacuum, ran out of space, cant bring up psql

I noticed I was running low on space on my system, so I found this vacuum
command. I ran it and it failed because it ran out of space:

vacuum mytable;
FATAL 2: ZeroFill failed to write
/var/lib/pgsql/data/pg_xlog/xlogtemp.23895: No space left on device
server closed the connection unexpectedly
This probably means the server terminated abnormally
before or while processing the request.
The connection to the server was lost. Attempting reset: NOTICE: Message
from PostgreSQL backend:
The Postmaster has informed me that some other backend
died abnormally and possibly corrupted shared memory.
I have rolled back the current transaction and am
going to terminate your database system connection and exit.
Please reconnect to the database system and repeat your query.

I cleared out that dir and then tried to go back into my database and I get
this error:

psql fsp
psql: could not connect to server: No such file or directory
Is the server running locally and accepting
connections on Unix domain socket "/tmp/.s.PGSQL.5432"?

Help?