Shell Programming and Scripting

Dears,

Can anyone advise how to log successful conditionals (unix commands) from any ksh script?

For example, the code is as follows:

if <command>
then
Block1 of statements
else
Block2 of statements
fi

What needed exactly is to log "Block1 of statements" if its conditon is met.

Thanks for your feedback

I can suggest something for BASH, hope this helps.

...
LOGFILE="./logf.out"
NUM=$1

f_LOG() {
echo "`date`:$@" >> $LOGFILE
}

f_INFO() {
echo "$@"
f_LOG "INFO: $@"
}

f_ERROR() {
echo "$@"
f_LOG "ERROR: $@"
}


if [ $NUM -eq 4 ]; then
f_INFO "4 is my lucky number"
f_INFO "Thanks for using my script"
else
f_ERROR "You are not good in choosing a lucky number"
fi

Executing:

$ ./logg.sh 3
You are not good in choosing a lucky number

$ cat logf.out
Mon Dec 17 19:04:19 IST 2007:ERROR: You are not good in choosing a lucky number

$ ./logg.sh 4
4 is my lucky number
Thanks for using my script

$ cat logf.out
Mon Dec 17 19:04:19 IST 2007:ERROR: You are not good in choosing a lucky number
Mon Dec 17 19:04:41 IST 2007:INFO: 4 is my lucky number
Mon Dec 17 19:04:41 IST 2007:INFO: Thanks for using my script

//Jadu

After executing a command, the result code can be obtained by using the variable $?

for example

command1
RES=$?

if [ $RES -ne 0 ]
then
echo "Error launch command"
else
echo "Command was succesful"
fi

Or :
if [[ $? -eq 0 ]] ; then
echo "Success " >> $LOG
else
echo $? " return value of $? Some failure " >> $LOG
exit 1
fi

I find it's handy to create a Log() function, to keep the messges format consistent and also allow output to several places and/or options.

I write something like:

Code:

#!/bin/ksh
# myscript

# Globals.
PROG=${0##*/}
LOGFILE=/var/tmp/mylog.txt

# Function to do logging.
Log()
{
  timestamp=`date '+%Y%m%d.%H%M%s'`
  echo "[$PROG.$timestamp] $*" >> $LOGFILE
}

# your code...
if [ ..... ]
then
  Log "It was successful"
else
  Log "Oh no!"
fi

You can then have logic in the Log function to raise OpenView alerts, send emails, write to syslog, or whatever, without having to trawl through your entire script looking at each echo command.