07-18-2008
assuming perl........
not sure if this is the source of your problem, but the @ symbol is being interpolated as an array because you have it inside a double-quoted string, use single-quotes:
$ssh = 'ssh username@host';
also, when you use exec in perl it does not return back to the perl script, although I am not sure what happens when you run it in a forked process. Try system() or qx//. qx// returns process output back, system() does not. Look them up in the perl documentation.
Next time put Perl in your subject line if that is what you are using.
fork and exec : Perl
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LEARN ABOUT SUSE
dbd::gofer::transport::stream
DBD::Gofer::Transport::stream(3) User Contributed Perl Documentation DBD::Gofer::Transport::stream(3)
NAME
DBD::Gofer::Transport::stream - DBD::Gofer transport for stdio streaming
SYNOPSIS
DBI->connect('dbi:Gofer:transport=stream;url=ssh:username@host.example.com;dsn=dbi:...',...)
or, enable by setting the DBI_AUTOPROXY environment variable:
export DBI_AUTOPROXY='dbi:Gofer:transport=stream;url=ssh:username@host.example.com'
DESCRIPTION
Without the "url=" parameter it launches a subprocess as
perl -MDBI::Gofer::Transport::stream -e run_stdio_hex
and feeds requests into it and reads responses from it. But that's not very useful.
With a "url=ssh:username@host.example.com" parameter it uses ssh to launch the subprocess on a remote system. That's much more useful!
It gives you secure remote access to DBI databases on any system you can login to. Using ssh also gives you optional compression and many
other features (see the ssh manual for how to configure that and many other options via ~/.ssh/config file).
The actual command invoked is something like:
ssh -xq ssh:username@host.example.com bash -c $setup $run
where $run is the command shown above, and $command is
. .bash_profile 2>/dev/null || . .bash_login 2>/dev/null || . .profile 2>/dev/null; exec "$@"
which is trying (in a limited and fairly unportable way) to setup the environment (PATH, PERL5LIB etc) as it would be if you had logged in
to that system.
The ""perl"" used in the command will default to the value of $^X when not using ssh. On most systems that's the full path to the perl
that's currently executing.
PERSISTENCE
Currently gofer stream connections persist (remain connected) after all database handles have been disconnected. This makes later
connections in the same process very fast.
Currently up to 5 different gofer stream connections (based on url) can persist. If more than 5 are in the cache when a new connection is
made then the cache is cleared before adding the new connection. Simple but effective.
TO DO
Document go_perl attribute
Automatically reconnect (within reason) if there's a transport error.
Decide on default for persistent connection - on or off? limits? ttl?
AUTHOR
Tim Bunce, <http://www.tim.bunce.name>
LICENCE AND COPYRIGHT
Copyright (c) 2007, Tim Bunce, Ireland. All rights reserved.
This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See perlartistic.
SEE ALSO
DBD::Gofer::Transport::Base
DBD::Gofer
perl v5.12.1 2008-03-10 DBD::Gofer::Transport::stream(3)