Blank File

ImpalaSS has asked for the wisdom of the Perl Monks concerning the following question:

Hello,
This is a little bit of code in the script I am currently working on. Here is my problem, when i print it using just print and the info, it prints on the command line perfectly, like this,

5213aud|5210|PPA0200ScrubOak|5213
5223aud|5222|PPA0366HighKnobMtn|5223
5224aud|5222|PPA0366HighKnobMtn|5224
5225aud|5222|PPA0366HighKnobMtn|5225
5227aud|5226|PPA0101Greentown|5227
5228aud|5226|PPA0101Greentown|5228
5229aud|5226|PPA0101Greentown|5229
5231aud|5230|PPA0221MtYeager|5231
5232aud|5230|PPA0221MtYeager|5232
5233aud|5230|PPA0221MtYeager|5233
5235aud|5234|PPA0231Freeland|5235
5236aud|5234|PPA0231Freeland|5236
5237aud|5234|PPA0231Freeland|5237
5239aud|5238|PPA0034TylerCorner|5239
5240aud|5238|PPA0034TylerCorner|5240
5241aud|5238|PPA0034TylerCorner|5241
5243aud|5242|PPA0209Scranton|5243
5244aud|5242|PPA0209Scranton|5244
[download]

only about 1200 of them. But, when i try and print to a file, the file it creats comes up blank? Any suggestions?


@omcees = ("pasys","audsys");

foreach $omc(@omcees){
    if ($omc eq "pasys"){$id = "pa"}
        else{$id = "aud";}
    $filename = "combine".".txt";
    ## May as well test them all now
    open(FIRST,  "/mnt/$omc/ne_data/unload_stats/$currenttime/cel_ntid
+.unl") or die "Could not open first\n";
    open(SECOND, "/mnt/$omc/ne_data/unload_stats/$currenttime/sit_ntid
+.unl") or die "Could not open second\n";
    if ($omc eq "pasys"){
        open(THIRD,  ">/tmp/$filename" ) or die "Could not write third
+\n";
    }
    else{
        open(THIRD,  ">>/tmp/$filename" ) or die "Could not write thir
+d\n";
    }
    
    my (%first, %found);
    while(<FIRST>) {
        my ($key, @cols) = split(m#\|# => $_, -1);
          push(@{$first{$key}}, \@cols);
          $found{$key} = $.;
    }
    close(FIRST);

    while(<SECOND>) {
          my ($one, $key, @cols) = split(m#\|# => $_, -1);
          if (exists $first{$key}) {
                delete $found{$key};
                for (@{$first{$key}}) {
                    
                  print THIRD $_->[0].$id."|$key|$cols[0]";
                  print THIRD "|".$_->[0]; 
                  print THIRD "\n";
              }
          }
     }
     
    close(SECOND);
    close(THIRD);
}
[download]

Thanks :)

Dipul

Comment on Blank File Select or Download Code

Replies are listed 'Best First'.
Re: Blank File by tadman (Prior) on Jan 25, 2001 at 23:44 UTC
Maybe it's just me, but your use of split() is a little unusual: `... = split(m#\\|# => $_, -1);` It's not entirely clear why you're using the arrow '=>' operator in there when a comma should do just fine. Also, including a negative number as a parameter seems to request the default behaviour, so it seems redundant and misleading. `... = split(m#\\|#);` Since you're using $_ anyway, and the default behaviour, you should be able to reference split as such. With respect to your curious problem, it's not clear why reorganizing the statements would cause the program to start "working" all of a sudden, but you could certainly avoid using concatenation and use the list method of print instead: `print THIRD $_->[0],$id,"\|",$key,"\|",$cols[0],"\|",$_->[0],"\n";` That would seem to be functionally equivalent, and more presentable.	[reply] [d/l] [select]
split,,-1 (Re: Blank File) by tye (Sage) on Jan 25, 2001 at 23:47 UTC
Specifying -1 as the third argument to split causes it to not discard trailing empty results, which is not the default behavior. - tye (but my friends call me "Tye")	[reply]
Re: split,,-1 (Re: Blank File) by tadman (Prior) on Jan 26, 2001 at 00:01 UTC
True, but the presence or absence of '-1' as a paremeter as used in that program would have no effect, correct? If I understand the documentation correctly, the '-1' is important in very specific circumstances, such as using pop(): `my ($a) = "the\|sneaky\|camel\|\|"; my (@b, $nil); # Try different parameters with split and report for my $p (undef, -1) { @b = split (/\\|/, $a, $p); ($nil) = pop (@b); print "split() with '$p': '$nil' should be empty, ", (length($nil)?" but isn't":"and is"),".\n"; }` [download] You learn something new every day, it seems.	[reply] [d/l]
Re: Blank File by ImpalaSS (Monk) on Jan 25, 2001 at 22:18 UTC
Oh yes, One more thing. When I had the print statements in this order: `print THIRD "$_->[0]\|$key\|$cols[0]"; print THIRD $_->[0].$id; print THIRD "\n";` [download] the code worked flawlessly. I hope this helps somewhat. Thanks Dipul	[reply] [d/l]


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