PS: the script should only contain the following:

#!/bin/sh

 RESULT=`ps x |grep -v grep |grep -c "tcpser"`

if [ $RESULT = 0 ]; then
    tcpser -s 2400 -d /dev/ttyUSB0 &


Nothing more.

I put the script into a file in the directory.  If you need it, you can
copy it directly to your pi with a wget command.

CVh

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