"Interrupt requested" in postgresql-DAY.log

Hi,

I have a PostgreSQL 9.3.4 database running on CentOS 6 with PostGIS 2.1.2. Each night, I run a cron job to dump (pg_dump) a few schemas for development snapshots. Everything runs without error.

However, it seems that the dump process consistently results in a single line in the postgresql-*.log file. Oddly enough, this entry seems to ignore the log_line_prefix configuration parameter.

postgres(at)db:/var/lib/pgsql/9.3/data $ cat pg_log/postgresql-Fri.log
Interrupt requested
postgres(at)db:/var/lib/pgsql/9.3/data $ grep log_line_prefix postgresql.conf
log_line_prefix = '< %t > ' # special values:
postgres(at)db:/var/lib/pgsql/9.3/data $ psql
psql (9.3.4)
Type "help" for help.

postgres=# show log_line_prefix;
log_line_prefix
-----------------
< %t >
(1 row)

postgres=# \q

Any ideas where this could be coming from and why it isn’t prefixed?

Thanks,
Louis