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

Hello Monks,

I am looking for a more efficient way of writing from a file handle. What I am doing is opening a dat file and printing it to a webpage. This is how I've been doing it so far. 
open (AP_MENU, "/web/aps/ap_menu.dat") or die "Cannot open: $!";
@fileinput_ap = <AP_MENU>;
for ($i = 0; $i <= $#fileinput_ap; $i++)  { print "$fileinput_ap[$i]" 
+}
close (AP_MENU) or die "Cannot close: $!";

[download]
Is there a more efficient way than reading everything into an array?

Replies are listed 'Best First'.
Re: Printing From a File Handle
by haoess (Curate) on Apr 28, 2004 at 20:22 UTC 
    @fileinput_ap = <AP_MENU>;
for ($i = 0; $i <= $#fileinput_ap; $i++)  { print "$fileinput_ap[$i]" 
+}

    [download]

    This can be done more perlish:

    while( <AP_MENU> ) {
  print;
}

    [download]
    or shorter: 
    print while <AP_MENU>;

    [download]

    If you just want to print an entire file, you can use print in array context

    print <AP_MENU>;

    [download]
    -- Frank
[reply]
[d/l]
[select]
      Is there anyway to add html formatting to it? e.g. 
      print while "<AP_MENU><br>";

      [download]
[reply]
[d/l]
        TIMTOWTDI: 
        # shortest
print "$_<br />" while <AP_MENU>;

# show what you mean
{
  local $\ = "<br />";
  print while <AP_MENU>;
}

# more readable?
foreach my $line (<FILE>) {
  print $line, "<br />";
}

        [download]
        -- Frank
[reply]
[d/l]

        Still more ways to do it: 

          # list processing
  print map "$_<br />", <AP_MENU>;

  # more abuse of special variables
  {
      local $, = "<br />";
      print <AP_MENU>, '';
  }

        [download]

        If you are reading in any old file for display in an HTML page, you will want to do at least minimal escaping of special characters, too: 

          while ( <AP_MENU> )
  {
      # protect against most egregious HTML violations
      s/&/&amp;/g; s/</&lt;/g; s/>/&gt;/g;

      # remove trailing whitespace so the <br /> is on
      # the same line as main text
      s/\s+$//;

      print "$_<br />\n";
  }

        [download]
[reply]
[d/l]
[select]
        #!/usr/bin/perl

print "Content-type: text/html\n\n";
print <<top;
<html>
<head><title>Some Title</title></head>
<body bgcolor="#000000">
top

print "<font color=\"#FFFFFF\">$_</font><br>" for <DATA>;

print <<bottom;
</body>
</html>
bottom

__DATA__
Test
Test Again
One More Test!

        [download]
        You can see it work here.

        www.perlskripts.com
[reply]
[d/l]
      while ( <LOG> ) { print "$_<br>" } does the trick.
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[d/l]
Re: Printing From a File Handle
by b10m (Vicar) on Apr 28, 2004 at 20:14 UTC

    This is a way:

    open AP_MENU, "</web/aps/ap_menu.dat" or die "Cannot open: $!";
print <AP_MENU>;
close AP_MENU or die "Cannot close: $!";

    [download]
    --
    b10m

    All code is usually tested, but rarely trusted.
[reply]
[d/l]
      or print while <AP_MENU>; to avoid whole-file slurp-and-dump.
      The PerlMonk tr/// Advocate
[reply]
[d/l]
Re: Printing From a File Handle
by Anomynous Monk (Scribe) on Apr 28, 2004 at 22:52 UTC
[reply]
[d/l]

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