Re: Reading File

[Karen Liew Ying Ping]

Hi Connie,

what's your $PrevEOL?
did you declare it somewhere?

sorry i'm still a very beginning beginner in PERL

thanks.

  ----- Original Message ----- 
  From: Connie Chan 
  To: Timothy Johnson ; 'Karen Liew Ying Ping ' ; [EMAIL PROTECTED] ; David vd Geer 
Inhuur tbv IPlib 
  Sent: Tuesday, June 25, 2002 12:51 AM
  Subject: Re: Reading File


  Hi everybody,

  I've done a dummy test, and finalized that David's method is the
  Goal Method, that's really Really Very Great !!!

  I've made a 50MB Text file ( Fixed length, 1001 char per line, with \n)
  for this test, and have the following results :

  #### SCRIPT 1 ##### Suggested by Johnson
  $start = time;
  open (FH, "text.txt");
  while (<FH>) { $data = $_ }
  close (FH);
  $end = time - $start;
  print $end."\n";
  ###### END WITH 8 SECs #######

  ##### SCRIPT 2 #### Suggested by myself
  $start = time;
  open (FH, "text.txt");
  @FD = <FH>;
  close (FH);
  $data = $FD[$#FD];
  $end = time - $start;
  print $end."\n";
  ###### END WITH 8 SECs #######

  ##### SCRIPT 3 #####  Suggested by David ( I've completing it =))
  $start = time;
  open (FH, "text.txt");
  seek (FH,0,2); ## I use 0 here as I assume the last line is not /^\n$/
  $curpos = tell(FH);
  while (! $PrevEOL)
  {   $data = <FH>;
       if ($data !~ /\n$/) { $curpos -- ; seek (FH, $curpos, 0);  }
       else { $PrevEOL = 1 }
  }
  $data = <FH>; close (FH);
  $end = time - $start;
  print $end."\n";
  ###### END WITH 0 SEC ( Actually 0.0x Sec) #######

  Please don't alarm me for omitted to use my , strict and -wT here,
  I will use them for doing my own script =)

  Besides, even though the time consume for Johnson's one and mine
  one are the same (nearly), however, it's better for try Johnson's one.
  That's beacuse if there are 5 or more clients query this File at the same
  time, mine one will surely halt the system (WinMe).

  Wish you have a nice day,
  Smiley Connie =)



  ----- Original Message -----
  From: "David vd Geer Inhuur tbv IPlib" <[EMAIL PROTECTED]>
  To: <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]>
  Sent: Monday, June 24, 2002 7:35 PM
  Subject: Re: Reading File


  >
  > I am try-ing to work something out with seek for you, but just can't find
  it yet.
  > This is how far I am yet :
  >
  > #!/usr/bin/perl
  >
  > use strict;
  >
  > my $file = "...";
  >
  > open(FH, "<$file");
  > seek(FH,2,2);
  > my $curpos = tell(FH); $_ = <FH>;
  > my $lastline = <FH>;
  > close(FH);
  >
  > print "$lastline \n";
  > print "$curpos \n";
  > # --------------
  >
  > As the seek brings me to the end of the file at the last character I cant
  print
  > the current line.
  > I will be looking further, there must be a beatifull way to do this.
  >
  > Regs David
  > ----------------
  > >
  > > open (FILE, "yourfile.txt");
  > > my @FD = <FILE>;
  > > close (FILE);
  > >
  > > my $lastline = $FD[$#FD]
  > >
  > > Hope this help,
  > > Smiley Connie =)
  > >
  > >
  > > ----- Original Message -----
  > > From: "Karen Liew Ying Ping" <[EMAIL PROTECTED]>
  > > To: <[EMAIL PROTECTED]>
  > > Sent: Monday, June 24, 2002 6:05 PM
  > > Subject: Reading File
  > >
  > >
  > > Hi,
  > >
  > > Let's say I'm opening a file.
  > > How do I read the last line of the file?
  > > is there any function in doing so?
  > >
  > > Thanks.
  > >
  > >
  > >
  > >
  > > --
  > > To unsubscribe, e-mail: [EMAIL PROTECTED]
  > > For additional commands, e-mail: [EMAIL PROTECTED]
  > >
  > >
  >


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