insert char(1) type by different ways.

Good day.

System Configuration
---------------------
  Architecture: Intel Pentium

  Operating System: 4.2-STABLE FreeBSD

  PostgreSQL version:   PostgreSQL-7.0.2

  Compiler used:  gcc 2.95.2

Description of problem
----------------------

It's some differences in results, then I inserted char(1) type. I introduce one
example:

create table ku(n_pp int4, col char(1));

insert into ku values(1, '\000');
insert into ku values(2, '\040');
insert into ku values(3, ichar(0));
insert into ku values(4, ichar(32));

select n_pp, ascii(col) from ku ;
 n_pp | ascii
------+-------
    1 |    32
    2 |    32
    3 |     0
    4 |    32
(4 rows)

Look at the strings where "n_pp" equal 1 and 2. "Col" column always equals to 32
(decimal), but I inserted as '\000' and '\040'. (It is first way).
  In second way, If I use ichar() function, then "col" column has another
values. This result is correct (I think).
Is it right ?
  Locales for "postgres" user adjust properly (if it's necessary).

ps. I use some function from list, which generated by "\df" command from psql
console. But I didn't found them in pgsql documentation. Is it possible that
this function will be removed in future version of postgresql ?
pps. Can I take description of this function ?
  sorry for my bad english ;)


  Regards..
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