Hi, I need to solve the following: there are a bunch of perl scripts calling a subroutine
WriteToLog all over the place. IT basically prints out the status of the program flow with time stamp and some other info
into a log file. But I only want those info for certain actions not always and I have identified where those 2 points
are. The WirteToLog is just too noisy. I am thinking of intercepting the WriteToLog call and with a flag, If the flag
is on it prints to log file, it not skips. I do not have access to WriteToLog source code. only the interface.
How to do this? the script layout: file a.pl

sub func1{
WriteTOLog($Arga,$Argb,$Argc,$Argd); }
 ... do a bunch of things 
<code>
file b.pl
<code>
sub func2{
WriteTOLog($Arga,$Argb,$Argc,$Argd); }
 ... do a bunch of things 
<code>
file c.pl
<code>
sub func3{
WriteTOLog($Arga,$Argb,$Argc,$Argd); }
 ... do a bunch of things 
<code>
file log.pl
<code>
sub WriteToLog($,$,$,$){
  local ($var) = @_;
  # do its fike IO stuff
}
[download]

so can I change WriteTOLog to:

sub MyWriteToLog($,$,$,$){
  if ($FLAG eq 1) {
  local ($var) = @_;
  # do its fike IO stuff
    WriteTOLog($a,$b,$c,$d);
  } else {
   #do nothing or other things;
  }
}
[download]

how to make those proginal files call MyWriteToLog when they see WriteTOLog? D I really have to change all these files?

2006-02-10 Retitled by broquaint, as per Monastery guidelines
Original title: 'intercept soub routine calls'