How to create csv file using shell script

You may just do:

echo "$host, `date`, checkout,$Time_checkout" >> log.csv
echo "$host, `date`, add, $Time_add" >> log.csv
echo "$host, `date`, cimmit, $Time_commits" >> log.csv

you can try something like this;

printf "Host\tDate\tOperation\tDuration\n" >> log.csv
printf "$host\t$(date)\tTime Taken to checkout\t$Time_checkout\n" >> log.csv
printf "$host\t$(date)\tTime Taken to add $loopmax 10MB svn files\t$Time_add\n" >> log.csv
printf "$host\t$(date)\tTime Taken to commit $loopmax 10MB svn files\t$Time_commit\n" >> log.csv

Just in case anyone is looking for CSV where values are in double quotes ("), you have to remove the outer quotes for the echo and use them (escaped) for each value instead, like this:

echo \"$host\",\"$date",\"checkout\",\"$checkout_time\" >> log.csv
echo \"$host\",\"$date",\"add\",\"$add_time\" >> log.csv
echo \"$host\",\"$date",\"commit\",\"$commit_time\" >> log.csv

I'd recommend writing a function to make your script less verbose and easier to read, like this.

write_csv(){
    echo \"$1\",\"$2\",\"$3\",\"$4\" >> log.csv
}
write_csv $host $date checkout $checkout_time
write_csv $host $date add $add_time
write_csv $host $date commit $commit_time

You can also generalize Mig82's answer to support variable arguments like this:

# Usage: csv <items>

csv()
{
    local items=("$@")

    (
    IFS=,
    echo "${items[*]}"
    )
}

csv 1 "2 3" >> log.csv

used the answer from @Nishant with a slight adjustment to handle quoting:

    csv()
    {
        local items=("$@")
    
        # quote and escape as needed
        # https://datatracker.ietf.org/doc/html/rfc4180
        for i in "${!items[@]}"
        do
            if [[ "${items[$i]}" =~ [,\"] ]]
            then
                items[$i]=\"$(echo -n "${items[$i]}" | sed s/\"/\"\"/g)\"
            fi
        done
    
        (
        IFS=,
        echo "${items[*]}"
        )
    }