Append to a file (from the beginning).

Comments

• DrGonzo

  December 2001

  heres a simple solution
  
  lets say your chat file is called ChatLog.txt.
  
  Copy ChatLog.txt to a file called ChatLog.old
  Then open ChatLog.txt for a write and print the new text into it then open the .old file and print that text into the new ChatLog.txt.
  
  want some code??
  
  sub CreateOldFile
  {
  my $file_fame = $_[0];
  my $newname = substr($file_name, 0, rindex($file_name ,'.')) . '.old';
  my $file_data;
  
  open(COFINPUTFILE, "< $file_name");
  open(COFOUTPUTFILE, "> $newname");
  chmod(0777, $newname);
  while($file_data = )
  {
  print COFOUTPUTFILE $file_data;
  }
  close(COFOUTPUTFILE);
  close(COFINPUTFILE);
  
  return($newname);
  }
  my $new_text = "new text or form value";
  my $file_name = "ChatLog.txt";
  my $oldfile_name = CreateOldFile($file_name); #Copys file to a file called $file_name.old and returns the name
  my $file_data;
  
  open(CHATLOG, "> $file_name");
  open(OLDCHATLOG, "< $oldfile_name");
  select CHATLOG; #pipe output to CHATLOG handle
  print $new_text . "
  ";
  while($file_data = )
  {
  print $file_data;
  }
  select STDOUT;
  close(OLDCHATLOG);
  close(CHATLOG);
  
  If that code isn't extremely easy for you to understand, then use it as best you can and go get a good book on PERL.
  
• Unknown

  February 2002

  hey,
  
  there is an eaier way to do it, but DrGonzos way is a safer way, anyway the easy way is to read the whole file into a scalar, add what u want to the end and then write it out again, eg:
  
  [code]
  open(INFILE,"data.txt") || die;
  while() { $buffer .= $_; }
  close(INFILE);
  
  $buffer = "Put here what you want at the start
  " . $buffer;
  
  open(OUTFILE,">data.txt") || die;
  print OUTFILE $buffer;
  close(OUTFILE);
  [/code]
  
  sorry im on windoze at the moment so i cant test the code but it all looks right, just make sure that you use DrGonzos method when the file starts getting into the megabytes range
  
• superjoe30

  September 2002

  
  : I need the program to append to the beginning of the file. Not the end. But sysseek or seek won't let you WRITE to the file, only read from the point you specify. How can I write to the beginning?
  :
  
  You could also do this:
  1.) read the file into an array
  2.) use shift() to append it
  3.) write the file
  
  [b]Code:[/b]
  [code]
  open(FH, $filetoappend) || die "Couldn't open $filetoappend: $!";
  my @file = ;
  close(FH);
  shift @file, $appenddata;
  open(FH, ">$filetoappend") || die "Couldn't open $filetoappend: $!";
  foreach (@file){
  print FH $_;
  }
  close(FH);
  [/code]
  
  
  [hr]
  ~~[blue]Perl[/blue]~~[red]Visual Basic[/red]~~[green]JavaScript[/green]~~
  SuperJoe
  
  
• helihopper

  January 2009

  your code works but i may be doing something wrong
  can u check it for me? i am getting extra
  data printed out to the file:
  
  http://pwinquist.com/blog.html
  
  here is the perl:
  #!/usr/local/bin/perl -w
  
  print "Content-type:text/html
  
  ";
  
  read(STDIN, $buffer, $ENV{'CONTENT_LENGTH'});
  @pairs = split(/&/, $buffer);
  foreach $pair (@pairs) {
  ($name, $value) = split(/=/, $pair);
  $value =~ tr/+/ /;
  $value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C", hex($1))/eg;
  $FORM{$name} = $value;
  }
  
  foreach $key (keys(%FORM)) {
  "$key = $FORM{$key}
  ";
  }
  
  #print MAIL "Hello Dudes . . .
  ";
  
  # print MAIL "$FORM{int1}
  ";
  # print MAIL "$FORM{int1}
  ";
  
  $now = localtime time;
  # print "It is now $now
  ";
  
  
  $test1 = $FORM{comments};
  
  $test2 = $FORM{name};
  
  open(INFILE,"output7.txt") || die;
  while() { $buffer .= $_; }
  close(INFILE);
  
  $buffer = "
  
  $now
  $test2
  
  says:
  $test1
  
  -------------------------------------------------------------------------------------------------------------------------------------
  
  " . $buffer;
  
  open(OUTFILE,">output7.txt") || die;
  print OUTFILE $buffer;
  close(OUTFILE);
  
  #reading
  open(OUTFILE, "output7.txt") || die "Opening output7.txt: $!";
  @test10=;
  close(OUTFILE);
  
  print
  Opinion
  
  
  Return to Las Vegas Sins & Scams.

  @test10 $buffer

  Return to Las Vegas Sins & Scams.
  
  

  ---

  
  
  
  
  
  EndHTML
  ;
  
  sub dienice {
  ($errmsg) = @_;
  print "

  Error

  ";
  print "$errmsg

  
  ";
  print "
  ";
  exit;
  }
  
  
  thanks
  
• helihopper

  January 2009

  your code works but i may be doing something wrong
  can u check it for me? i am getting extra
  data printed out to the file:
  
  http://pwinquist.com/blog.html
  
  here is the perl:
  #!/usr/local/bin/perl -w
  
  print "Content-type:text/html
  
  ";
  
  read(STDIN, $buffer, $ENV{'CONTENT_LENGTH'});
  @pairs = split(/&/, $buffer);
  foreach $pair (@pairs) {
  ($name, $value) = split(/=/, $pair);
  $value =~ tr/+/ /;
  $value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C", hex($1))/eg;
  $FORM{$name} = $value;
  }
  
  foreach $key (keys(%FORM)) {
  "$key = $FORM{$key}
  ";
  }
  
  #print MAIL "Hello Dudes . . .
  ";
  
  # print MAIL "$FORM{int1}
  ";
  # print MAIL "$FORM{int1}
  ";
  
  $now = localtime time;
  # print "It is now $now
  ";
  
  
  $test1 = $FORM{comments};
  
  $test2 = $FORM{name};
  
  open(INFILE,"output7.txt") || die;
  while() { $buffer .= $_; }
  close(INFILE);
  
  $buffer = "
  
  $now
  $test2
  
  says:
  $test1
  
  -------------------------------------------------------------------------------------------------------------------------------------
  
  " . $buffer;
  
  open(OUTFILE,">output7.txt") || die;
  print OUTFILE $buffer;
  close(OUTFILE);
  
  #reading
  open(OUTFILE, "output7.txt") || die "Opening output7.txt: $!";
  @test10=;
  close(OUTFILE);
  
  print
  Opinion
  
  
  Return to Las Vegas Sins & Scams.

  @test10 $buffer

  Return to Las Vegas Sins & Scams.
  
  

  ---

  
  
  
  
  
  EndHTML
  ;
  
  sub dienice {
  ($errmsg) = @_;
  print "

  Error

  ";
  print "$errmsg

  
  ";
  print "
  ";
  exit;
  }
  
  
  thanks