possible bug in COPY ... FROM ... NULL '\0'

The documentation says:

"The specified null string is sent by COPY TO without adding any
backslashes; conversely, COPY FROM matches the input against the null
string before removing backslashes."
-- http://www.postgresql.org/docs/devel/static/sql-copy.html

Those seem inconsistent with the following behavior:

postgres=# copy foo to '/tmp/a.copy' null '\0';
COPY 2
postgres=# copy foo from '/tmp/a.copy' null '\0';
ERROR: invalid byte sequence for encoding "UTF8": 0x00
CONTEXT: COPY foo, line 2: "\0"

$ cat /tmp/a.copy
1
\0

COPY TO seems to follow the documentation, inserting the null string
without modification into the output file. COPY FROM seems to de-escape
the input before trying to match it against the null string, leading to
the invalid byte sequence.

standard_conforming_strings is on.

Regards,
Jeff Davis