Shell Programming and Scripting

  expr "trycnt + 1"
  if [ $trycnt -eq $maxtry ]; then
         boolean=0
         echo "tried $maxtry time.... giving up"
  fi

     else
  boolean=0
  fi
  done
  fi

$ expr "5" "+" "3"
8
$ expr "5 + 3"
5 + 3
$

v=1
v=`expr "$v" "+" "1"`

v=1
echo "v is $v"
((v=v+1))
echo "v is now $v"
echo "v plus one is $((v+1))"

#!/bin/bash

printf " ---------------------------------------------------------------------------------------------------\n" >> $SHEPHERD_INFO.$DATE
printf " File Name               : Status Of SHEPHERD Process `hostname` \n" >> $SHEPHERD_INFO.$DATE
printf " Author                  : Siddhesh Khavnekar \n" >> $SHEPHERD_INFO.$DATE
printf " Description             : Displays Information on AMS Shepherd Process\n" >> $SHEPHERD_INFO.$DATE
printf " Last Modified       : `date +%m/%d/%y` \n" >> $SHEPHERD_INFO.$DATE
printf " ----------------------------------------------------------------------------------------------------\n" >> $SHEPHERD_INFO.$DATE

maxtry=5
trycnt=0
SHEPHERD_INFO=/root/shepherd_pid
DATE=`date +%Y%m%d%H%M%S`
log_file="shepherd.$$.pid"
echo $DATE >> $SHEPHERD_INFO.$DATE

printf "\n\n################### Shepherd PID Before restart #######################\n\n" >>  $SHEPHERD_INFO.$DATE


present_pid=`ps -ef | grep shep-1 | grep -v grep | grep -v wls100ctl | awk '{print $2}'`
echo "$present_pid" >> $SHEPHERD_INFO.$DATE

sleep 10
sh /root/ams_rc stop_shepherd > /dev/null

if [ "$?" -eq "0" ]
then
sleep 30
sh /root/ams_rc start_shepherd > /dev/null
else
boolean=1
echo "Shepherd not stopped Properly" > /root/$log_file

#check the process again
#boolean : to run the while loop for 3 times before giving up. If the condition is satisfied and when the variable has zero value, then it comes out of loop

while [ $boolean ]
do
ps -ef | grep -v grep | grep -w $present_pid
if [ "$?" -eq "0" ]
then
sh /root/ams_rc stop_shepherd > /dev/null
sleep 30

expr "trycnt + 1"
if [ $trycnt -eq $maxtry ]; then
       boolean=0
       echo "tried $maxtry time.... giving up"
fi

else
boolean=0
fi
done
fi

sleep 30

printf "\n\n################### Shepherd PID After restart #######################\n\n" >>  $SHEPHERD_INFO.$DATE
ps -ef | grep shep-1 | grep -v grep | grep -v wls100ctl | awk '{print $2}' >> $SHEPHERD_INFO.$DATE
ps -ef | grep shep-1 | grep -v grep | grep -v wls100ctl | awk '{print $2}' >> /root/$log_file
echo "Shepherd Started" > /root/$log_file


#mail the log file
mail -s " shepherd Restart Status `date` " coreservicesvfnz@vodafone.com < /root/$log_file
mail -s " shepherd Restart Log `date` " coreservicesvfnz@vodafone.com < /root/shepherd_pid

exit 0

#!/bin/bash

# You are using $SHEPHERD_INFO and $DATE before you set them.
# This will cause errors or weird named files.  Move the statements up here:
SHEPHERD_INFO=/root/shepherd_pid
DATE=`date +%Y%m%d%H%M%S`

# If you're printing dozens of statements to the same destination, a
# redirection would be more efficient, done like this:


exec 5<&1  # save stdout in case you want it back
exec 1>$SHEPHERD_INFO.$DATE # make stdout go to $SHEPHERD_INFO.$DATE

#printf " ---------------------------------------------------------------------------------------------------\n" >> $SHEPHERD_INFO.$DATE
#printf " File Name               : Status Of SHEPHERD Process `hostname` \n" >> $SHEPHERD_INFO.$DATE
#printf " Author                  : Siddhesh Khavnekar \n" >> $SHEPHERD_INFO.$DATE
#printf " Description             : Displays Information on AMS Shepherd Process\n" >> $SHEPHERD_INFO.$DATE
#printf " Last Modified       : `date +%m/%d/%y` \n" >> $SHEPHERD_INFO.$DATE
#printf " ----------------------------------------------------------------------------------------------------\n" >> $SHEPHERD_INFO.$DATE

# For printing large chunks of data you can use a here-document, like this.
# Also, hostname is available as $HOSTNAME letting you avoid launching
# an external program.
cat <<EOF
---------------------------------------------------------------------------------------------------
 File Name               : Status Of SHEPHERD Process $HOSTNAME
 Author                  : Siddhesh Khavnekar
 Description             : Displays Information on AMS Shepherd Process
 Last Modified       : `date +%m/%d/%y`
----------------------------------------------------------------------------------------------------
EOF

maxtry=5
trycnt=0
log_file="shepherd.$$.pid"
echo $DATE

printf "\n\n################### Shepherd PID Before restart #######################\n\n"

# You can avoid needing grep -v grep by altering the first pattern a little.
# [s]hep does the same thing as shep but won't match grep '[s]hep-'.

# We also don't need to save this in a variable.  We can redirect it
# directly to where it's needed -- or not redirect it at all since we
# changed stdout earlier
ps -ef | grep '[s]hep-1 | grep -v wls100ctl | awk '{print $2}'`
# echo "$present_pid" >> $SHEPHERD_INFO.$DATE

sleep 10

# "something ; if [ $? -eq 0 ]" is equivalent to "if something".
# 

# sh /root/ams_rc stop_shepherd > /dev/null
# if [ "$?" -eq "0" ]
if sh /root/ams_rc stop_shepherd > /dev/null
then
        sleep 30
        sh /root/ams_rc start_shepherd > /dev/null
else
        boolean=1
        echo "Shepherd not stopped Properly" > /root/$log_file

#check the process again
#boolean : to run the while loop for 3 times before giving up. If the condition is satisfied and when the variable has zero value, then it comes out of loop

# while [ $boolean ] doesn't do what you think it does.
# the loop will never end.
# while [ "$boolean" -eq 1 ] is more what you wanted.
# But you don't even need a variable to end the loop, you can
# break it anywhere you want with break.
while true # loop forever
do
        ps -ef | grep -v grep | grep -w $present_pid > /dev/null
        if [ "$?" -eq "0" ]
        then
                sh /root/ams_rc stop_shepherd > /dev/null
                sleep 30

                # As my last post explained, expr doesn't work this way.
                # expr "trycnt + 1"
                trycnt=`expr "$trycnt" "+" "1"`
                
                if [ $trycnt -eq $maxtry ]; then
                        echo "tried $maxtry time.... giving up"
                        break
                fi
        else
                break
        fi
done
# Not sure what this extra fi was for.
# fi

sleep 30

cat <<EOF

printf "\n\n################### Shepherd PID After restart #######################\n\n"

ps -ef | grep '[s]hep-1' | grep -v grep | grep -v wls100ctl | awk '{print $2}'
ps -ef | grep '[s]hep-1 | grep -v grep | grep -v wls100ctl | awk '{print $2}' >> /root/$log_file
echo "Shepherd Started" > /root/$log_file


#mail the log file
mail -s " shepherd Restart Status `date` " coreservicesvfnz@vodafone.com < /root/$log_file
mail -s " shepherd Restart Log `date` " coreservicesvfnz@vodafone.com < /root/shepherd_pid

exit 0