#16 kernel 2.6, filter=on and using pipe (|)

[Anonymous]

Since I switched to kernel 2.6 there seems to be a
timing problem in connection with the filter option of
sqsh and redirection using the pipe '|'.

Normally we use the filter-option to log all queries,
so that disasters are likely to be recoverable.

\set filter_prog="/usr/bin/tee -a
$HOME/sqsh_${DSQUERY}.log"
\set filter=on

Unfortunately, when using a 2.6.X kernel and the pipe
to redirect output to 'less' or 'grep' the query never
(or only on _very_ rare occations) returns to prompt.

> select 1; | grep 'affected'
^C
>

setting 'filter=off' it works just fine:

> select 1; | grep 'affected'
(1 row affected)
>

Just for fun I ran strace on the sqsh while doing this
and suddenly the problem was gone! Now I updated to a
newer kernel (2.6.9) in hope the problem would vanish,
but now 'strace' doesn't solve the problem anymore ;)

my system:
Gentoo Linux: 1.4.16
Kernel: 2.6.9-gentoo-r4
Sqsh: sqsh-2.1 (linked with sybase-12.5 libraries!)

bonobo 'at' gmx.de
PS: when I boot a 2.4.X kernel, this problem does not
occur.