BLOBs containing NUL characters (ASCII 0) can be written to the
database, but they get truncated at the first NUL by lo_read
when they are read back. The reason for this is that lo_read in
Pg.xs is using the default:
OUTPUT:
RETVAL
buf
which uses C's strlen() to work out the length of the scalar.
The code ought to read something more like:
OUTPUT:
RETVAL
buf sv_setpvn((SV*)ST(2), buf, RETVAL);
I am not sure if this needs to be done on both lo_read methods
in this file, but I changed both and have not since had any
problems with truncated BLOBs.