...
open, etc...
my $File
{
local $/; 
$File=<FILE>;
}
...
[download]

ChOas

Once I encountered a problem concerning an exported peagasus mailfile. It was several hundreds of megabytes big. My oportunity was to split it into parts, each containing exactly one mail. As the file had a nice seperator, it seemed quite easy to me - but the first attempt blew up my memory. This was the first time I came to use the $_ variable instead of an own:


open(FH,"<$source") || die "cant open $source: $!\n";

while (<FH>){

    push @file, $_;

    if ($_ =~ /^-- End --/) {
        $zaehler++;

        open(GUN,">$destiny") || die "can write to $destinyfile$zaehle
+r:$!";

        foreach $zeile (@file) {

            print GUN $zeile;

        }#endforeach

        undef @file;

        close(GUN);

        print "$zaehler:\n";

    }#endif

}#endwhile

close(FH);
[download]


easy code, sent in the hope it helps you

there are no silly questions
killerhippy


Edit ar0n -- 2001-07-24 fixed excessive whitespace

There are no built-in length restrictions on Perl's strings; in practice, the limitation is how much of your system's memory is available to Perl (this is something your system administrator can set, so check local listings).

The most efficient ways of reading a whole file into a scalar involve unsetting the input record separator $/ and then reading in the file (by unsetting the separator, nothing counts as a break between lines, so to speak). A bit of code that does that is:

my $str;
{
    local $/; # sets $/ to undef only WITHIN the braces
    open FILE, $filename or die "Can't open $filename: $!\n";
    $str = <FILE>;
    close FILE:
}
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HTH.

perl -e 'print "How sweet does a rose smell? "; chomp ($n = <STDIN>); 
+$rose = "smells sweet to degree $n"; *other_name = *rose; print "$oth
+er_name\n"'
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$str = join ' ',<>;
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If you just want to slurp all the lines, concatenated (you usually don't want those spaces we just added):

{
  local $/;       # Temporarily set $/=undef: "total slurp mode"
  $str = <>;      # Slurp it all in one go!
}
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You're still working on your computer, though! So you cannot (or should not) read huge files into memory. Reading huge files into memory is grounds for LARTing on many systems!

How large is `huge' depends on your computer; it's almost certainly well below 2GB, though!

How large is `huge' depends on your computer; it's almost certainly well below 2GB, though!

You have seen my computer, haven't you?

scnr ;-)))

-- Hofmator

Be that as it may, I think using <> in array context is going to build up a huge AV temporary (Perl's internal representation of an array). Also, I have a sneaking suspicion the person would also like to get rid of the newlines of each record, in which case one would do something like:

  my $foo;
  while( <> ) {
    chomp; # maybe, maybe not, depending on the circumstances
    if( defined( $foo )) {
      $foo .= " $_";
    }
    else {
      $foo = $_;
    }
  }
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g r i n d e r

   open my $fh, $file_name or die "Cannot open $file_name $!";
   read $fh, my $str, -s $fh;
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