#the next 2 line have been assigned earler in the program from reading in the config file
$filter = "user (.*) has (logged on)";  
$output_string = "user $1 has accessed the system and is $2"; 



#this line has been read in from a log file
$log_string = "user bob has logged on"; 


# need to search the log string and format output string replacing $1 & $2
$output_string =~s/filter//g;
$output_string =~s/(\$\w+)/$1/eeg;


print "$output_string\n";