Re: Running iocsh in the background

[Dirk Zimoch <dirk.zimoch@psi.ch>]

Kevin M. Peterson wrote:
> I have a Linux IOC and I am using the main function from
> R3.14.1's example App.  After the IOC is initialized iocsh
> left in "interactive mode" just like the App. Dev. Guide
> describes.
>
> Unfortunately, "shutting down" the Linux IOC dangerously
> easy.  It isn't necessary to type the "exit" command; Closing
> the terminal window or pressing Ctrl-C do the job with even
> less effort.
>
> Is it possible to start the Linux IOC and have it run in the
> background?  The Linux IOC seems to be missing the
> "non-interacting mode" that all of the vxWorks IOCs have.

I have written a small tcl program (see attachment), that acts as a box 
for a shell (e.g. a Linux IOC) to run it in the background. Terminals 
programs can connect via TCP-IP (e.g. telnet). When the shell dies, it 
will be restarted automatically.

usage:  shellbox.tcl <TCP-port> <shellcommand> &

It is a quick an simple tool, thus there is no security. Everyone can 
log in and all input is merged to stdin of the shell. All stdout and 
stderr is distributed to everyone who is logged in.

To make live easier, I have also written a script (iocsh, attached), 
that creates a startup script on the fly from its command line arguments 
and starts a Linux IOC. To use it, you will have to adjust the pathnames 
 in the script :-(

Best regards
Dirk

--
Dr. Dirk Zimoch
Swiss Light Source
Paul Scherrer Institut
Computing and Controls
phone +41 56 310 5182
fax   +41 56 310 4413

Attachment: shellbox.tcl
Description: Tcl script

#!/bin/bash
if [ "$1" = -h ]
then
  echo "usage: iocsh [files]"
  echo "start an EPICS iocsh and load files"
  echo "recognized filetypes: *.db *.template *.subs *.dbd"
  echo "after *.db and *.template, you can specify substitutions with macro=value"
  echo "if a file is @filename, more arguments are read from filename"
  echo "all other files are taken as scripts to source"
  exit
fi
if [ "$1" = -v ]
then
  echo "iocsh by Dirk Zimoch"
  echo '$Source: /cvs/CVSROOT/UTILITIES/scripts/sh/iocsh,v $'
  echo '$Revision: 1.5 $'
  echo '$Date: 2002/12/19 08:55:23 $'
  exit
fi
export LD_LIBRARY_PATH=/devl/epics3.14.0.beta1/base/lib/linux-x86:$LD_LIBRARY_PATH
startup=$(mktemp /tmp/iocstartup.XXXXXX)

function loadFiles () {
while [ "$#" -gt 0 ]
do
  file=$1
  case $file in
    ( @* )               loadFiles $(cat ${file#@}) ;;
    ( *.db | *.template) subst=""
                         while [ "$#" -gt 1 ]
                         do
                            case $2 in 
                                ( *=* ) subst="$subst,$2"; shift ;;
                                ( * )   break ;;
                            esac
                         done
                         echo "dbLoadRecords (\"$file\", \"${subst#,}\")" ;;
    ( *.subs | *.subst ) echo "dbLoadTemplate (\"$file\")" ;;
    ( *.dbd )            echo "dbLoadDatabase (\"$file\")" ;;
    ( * )                echo "< $file" ;;
  esac
  shift
done
}

{
echo "dbLoadDatabase /devl/epics3.14.0.beta1/APPS/EPS/dbd/example.dbd"
echo "registerRecordDeviceDriver pdbbase"
loadFiles $*
echo "iocInit"
} >> $startup
trap "rm -f $startup" EXIT
softioc $startup 2>&1