LP #810356: reason of can not insert rows into myisam table using HandlerSocktet

**Reported in Launchpad by 林晓斌 last update 09-01-2013 04:17:52

I try to insert one row into a myisam table, use perl client written as
"my $res = $hs->open_index(0, 'test', 'sbtest', 'PRIMARY', 'id,k,c,pad');
$res = $hs->execute_single(0, '+', ["1", "100", "a", "b"], 1, 0);"

After run the script, the row can not be shown when "select * from sbtest", but the primary key is occupied.

It seems that when HandlerSocket call the "ha_myisam::write_row(buf)", the first byte of buff is not set correctly (set as 0).

If I change it to 0xff, the row can be insert into the table.