Decode Tomcat startup.sh script.

[Bruce Jin]

Decode Tomcat startup.sh script.

startup.sh contains these lines. Can anyone help explain what do they do? Thanks!


# resolve links - $0 may be a softlink
PRG="$0"

while [ -h "$PRG" ] ; do
ls=`ls -ld "$PRG"`
link=`expr "$ls" : '.*-> \(.*\)$'`
if expr "$link" : '.*/.*' > /dev/null; then
PRG="$link"
else
PRG=`dirname "$PRG"`/"$link"
fi
done

PRGDIR=`dirname "$PRG"`
EXECUTABLE=catalina.sh

# Check that target executable exists
if [ ! -x "$PRGDIR"/"$EXECUTABLE" ]; then
echo "Cannot find $PRGDIR/$EXECUTABLE"
echo "This file is needed to run this program"
exit 1
fi

exec "$PRGDIR"/"$EXECUTABLE" start "$@"