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Help needed for understanding a function

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# 1  
Old 03-06-2010
Help needed for understanding a function
There is a function called start:

Code:
start()
{
echo -n $"Sending Startup Email: "
echo "${RESTARTBODY}" | mutt -s "${RESTARTSUBJECT}" ${EMAIL}
RETVAL=$?

if [ ${RETVAL} -eq 0 ]; then
touch ${LOCKFILE}
success
else
failure
fi
echo
return ${RETVAL}
}

Can anyone explain what the bold part of the function means?
# 2  
Old 03-06-2010
Quote:
Originally Posted by proactiveaditya
There is a function called start:

(Code indented for easier comprehension.)
Quote:
Code:
start()
{
  echo -n $"Sending Startup Email: "
  echo "${RESTARTBODY}" | mutt -s "${RESTARTSUBJECT}" ${EMAIL}
  RETVAL=$?

  if [ ${RETVAL} -eq 0 ]; then
    touch ${LOCKFILE}
    success
  else
    failure
  fi
  echo
  return ${RETVAL}
}

Can anyone explain what the bold part of the function means?

It's either pseudocode or the commands success and failure are defined elsewhere.
# 3  
Old 03-07-2010
The entire script is:

Code:
#!/bin/bash

EMAIL="user@domain.com"
RESTARTSUBJECT="["`hostname`"] - System Startup"
SHUTDOWNSUBJECT="["`hostname`"] - System Shutdown"
RESTARTBODY="This is an automated message to notify you that "`hostname`" starte                                                                              d successfully.
Start up Date and Time: "`date`
SHUTDOWNBODY="This is an automated message to notify you that "`hostname`" is sh                                                                              utting down.
Shutdown Date and Time: "`date`
LOCKFILE=/var/lock/subsys/SystemEmail
RETVAL=0

# Source function library.
. /etc/init.d/functions

stop()
{
echo -n $"Sending Shutdown Email: "
echo "${SHUTDOWNBODY}" | mutt -s "${SHUTDOWNSUBJECT}" ${EMAIL}
RETVAL=$?

if [ ${RETVAL} -eq 0 ]; then
rm -f ${LOCKFILE}
success
else
failure
fi
echo
return ${RETVAL}
}

start()
{
echo -n $"Sending Startup Email: "
echo "${RESTARTBODY}" | mutt -s "${RESTARTSUBJECT}" ${EMAIL}
RETVAL=$?

if [ ${RETVAL} -eq 0 ]; then
touch ${LOCKFILE}
success
else
failure
fi
echo
return ${RETVAL}
}

case $1 in
stop)
stop
;;
start)
start
;;
*)
esac
exit ${RETVAL}

# 4  
Old 03-07-2010
The functions succes and failure are defined in the script:
Code:
/etc/init.d/functions

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