OT: help needed to debug Perl script

[M. Fioretti]

Greetings,

A few weeks ago I quickly put together a Perl script to parse big CSV 
files, for a project I am working on (I need to do this several times a 
day, always with new data). All was fine until yesterday, when the 
script started behaving in a consistent, but totally wrong way.

The script runs with "use strict" and -w switch, but I only get a few 
warnings for using uninitialized values in certain statements.

The relevant part of the code is this:

    147	my $keycounter = 1;
    148
    149	foreach my $qtq (sort keys %all) {
    150
    151	    printf "\nALLCHECK: %6.6s >> %s;\n", $keycounter, $qtq;
    152	    $keycounter++;
    153	}
    154
    155	 foreach my $qq (sort keys %all) {
    156	    $url = $qq;
    157	    print "\nADDINGURX: $url;\n";
    158	    print "\nADDINGURQ: $qq;\n";

lines 157, 158 and from 147 to 153 are added only for diagnostics. What 
happens is that, when I dump  the script output to a file, i.e.:

./myscript.pl > logfile

then:

a) logfile contains 26k+ lines starting with "ALLCHECK" = the %all hash 
contains 26k+ keys (

b) the *same* logfile contains:

    ~4700 lines starting with ADDINGURX
    ZERO lines starting with ADDINGURQ

in other words:

the script worked perfectly for weeks. Starting yesterday, the same 
script says in line 151 that
the hash has 26k keys, and 5 lines later, that the keys ofthe same hash 
are only 4700???

I honestly have no idea of what is happening, or of why it only started 
happening now. The input CSV files (which I cannot share, sorry, not my 
data...) are different every time, so I initially thought that the last 
ones contained some weird character that confuses my code. But if that 
were the case, even the first printing statement would only print ~4700 
lines.

So, any help is appreciated,

Thanks,
Marco