problem: using large objects from tcl

I am trying to use large objects from TCL. May I don't read the man
page right ...
TCL code:

#!/usr/local/pgsql/bin/pgtclsh

set CONN [pg_connect nccbor]

puts "create : [set LOID [pg_lo_creat $CONN "INV_READ|INV_WRITE"]]"

puts "open (w): [set LOFD [pg_lo_open $CONN $LOID w]]"
set STR "sdlfkjhlskdjfh lakjdhfljkadsfhlkjas"
set SIZ [string length $STR]
puts "write : [pg_lo_write $CONN $LOFD $STR $SIZ]"
puts "close : [pg_lo_close $CONN $LOFD]"

puts "open (r): [set LOFD [pg_lo_open $CONN $LOID r]]"
puts "read : [pg_lo_read $CONN $LOFD STR 10240]"
puts $STR
puts "close : [pg_lo_close $CONN $LOFD]"

pg_disconnect $CONN

Output of code :

./test_lo.tcl
create : 93377
open (w): 0
write : 35
close : -1
open (r): -1
read : -1
oid
close : -1

Does anyone know what I've done wrong?

--
the four stages of competence:

1 unconscious incompetence:
I don't even know that I don't know how to do X
2 conscious incompetence
I do know that I don't know how to do X
3 conscious competence
I do know how to X, but I have to think about it
4 unconscious competence
I know how to X and I do it without thinking about it

(Think of e.g. driving a car)

Kurt Seel, Systems Engineer
Unified Technologies Corp.
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