\section{Customizing Your Personal Yohkoh Working Environment}\index{customizing working environment}

This section briefly describes options available for customizing the Yohkoh data analysis
environment.  To gain a deeper understanding of the IDL related items listed here, the user 
is referred to to the IDL User's Guide, Chapter: RUNNING IDL.  

\subsection{Initial User Setup (.yslogin)} \label{newuser}\index{.yslogin}\index{setting up account}

For new user accounts, execute the following procedure one time.\footnote{
Since the Yohkoh Software at a site is often shared among many machines, we
supply an initialization script to dynamically define the location of the 
Yohkoh Software.  This will avoid workstation hangups when the Yohkoh server 
is down and also permits multiple Yohkoh hosts (page~\pageref{multi_host}).}
First, determine the location of the Yohkoh software at your
site.  Call this path {\it ysw}.
%
\ultrixinputa{setenv ys {\it ysw}}
\ultrixinputc{source \$ys/gen/script/ys\_newuser}

Once this procedure has been executed, the following command will define
the Yohkoh IDL environment:
%
\ultrixinputa{source  $\sim$/.yslogin}
%
Most users will find it convenient to have this Yohkoh setup done 
automatically as part of the login procedure.  For Ultrix and IRIX users, 
insert the line into your $\sim$/.login file.  Users of SUN, Mips, and most
others should insert the line into the $\sim$/.cshrc file.

\subsection{Running IDL (run\_idl)}\index{run\_idl}\index{IDL}\index{starting IDL}

The file \$ys/gen/setup/run\_idl is a script which performs the Yohkoh IDL 
startup procedure.  When working within the Yohkoh environment, this
script is run when a user enters the command {\tt idl}. The alias {\it idl} is 
defined during the execution of idl\_setup.

The following functions are performed by the run\_idl script:

\IItem
\item define the IDL SW !path (Concatenation of Yohkoh, Personal, and IDL paths)
\item setup remote X display if not already set (selected systems)
\item display message of the day
\item execute the Yohkoh wide IDL\_STARTUP
\item optionally execute user defined IDL\_STARTUP
\item enter IDL 
\end{itemize}

The following additional options are available by entering a second 
parameter on the command line:

\newpage
\begin{verbatim}
% idl nox       # bypass X windows setup - useful to avoid color table
                # corruption caused by 2nd IDL session or to speed up remote

% idl tek       # startup with plot device set to 'TEK' (Tektronics mode)

% idl noys      # do not include Yohkoh paths in IDL !path setup 
                # for non-Yohkoh IDL work(?!)

% idl fast      # define path from file (faster) [if supported at site]

% idl ahead     # place personal path ($IDL_PATH)  ahead of Yohkoh paths
                # in IDL !path variable - default is Yohkoh paths first
\end{verbatim}


\subsection{Personal SETUP\_YSENV}\index{setup\_ysenv}

Under Unix, the Yohkoh startup will automatically execute (source) a
script file in the users home directory which is named setup\_ysenv. 
This can be used to personalize the operating system environment.  One
simple use of this file would be to alter some of the Yohkoh
environmental startup defaults; see \$ys/gen/setup/setup\_ysenv for a
convenient template and documentation.  

\subsection{IDL\_PATH}\index{IDL\_PATH}

Users may define one or more personal paths which may be used in conjunction
with the extensive Yohkoh path definition.  This will permit use of
local and personal IDL libraries while still remaining within the Yohkoh
analysis framework.  To use this feature, the user should define the
Unix environmental or VMS logical: IDL\_PATH.  See the IDL User's Guide,
Chapter ``RUNNING IDL'' for a discussion of the Unix and VMS IDL\_PATH
syntax.  
An example of a command located in the {\tt .login} file which
will add all directories which have .PRO files
under /2p/morrison/soft and /usr/local/lib/idl/lib is:
%
\begin{verbatim}
           setenv IDL_PATH +/2p/morrison/soft:+/usr/local/lib/idl/lib
\end{verbatim}

\subsection{Personal IDL\_STARTUP}\index{IDL\_STARTUP}

Yohkoh users may define an IDL startup routine by defining the Unix
environmental or VMS logical IDL\_STARTUP.  An IDL startup is a file
which contains IDL commands.  These commands are automatically executed
at startup time to allow customization of the IDL environment.  If
IDL\_STARTUP is defined, it is executed after the Yohkoh-wide and site 
IDL\_STARTUP files so the user values will supercede the defaults. 
An example of a command located in the {\tt .login} file which
will cause the IDL commands in {\tt /2p/morrison/idl\_startup.pro}
to be executed when IDL starts is:
%
\begin{verbatim}
           setenv IDL_STARTUP /2p/morrison/idl_startup.pro
\end{verbatim}

\subsection{Multiple SW Host capability}

See the description on page~\pageref{multi_host} for details on how to
set up your system so that it can use a backup machine in the case when
the primary machine is unavailable.

\subsection{Switch between primary and backup Yohkoh Hosts}
\index{idlback}\index{idlnorm}\index{switching Yohkoh hosts}\index{Yohkoh hosts, switching}

For sites which support multiple software hosts, the following Unix
commands are available.  Switch to the backup host can be done for
backup system testing or in the event that the primary host has `gone
down' after your session has already started (automatic host selection
is done when your session starts)
%
\ultrixinputA{3}{idlback}{ \# select backup host}
\ultrixinputC{3}{idlnorm}{ \# select primary host (startup value)}

\subsection{setenv DISPLAY}

It is possible to log onto a remote machine to run IDL and to have the
X-window display redirected back to your local machine.  See the description
in the Appendix of the User's Guide for details for the necessary commands.
