Re: read a file in both directions

Well, the first part is easy:

open FILE, "path/to/file";
local $/ = "\n\n";
my $first_part = <FILE>;
[download]

That would work great if you only needed the first part. But since you want the second part also, unless you are working with HUGE files, I think it's better (more efficient) to read it into memory and then play with it.

open FILE, "path/to/file";
local $/ = undef;
my $whole_file = <FILE>;

my $first_blank_pos = index($whole_file,"\n\n")
die "no blank lines" 
  unless ($first_blank >= 0)

my $first_part = 
  substr $whole_file, 0, $first_blank_pos;

my $second_part = 
  reverse substr $whole_file, $first_blank_pos;
[download]

That will do it all in memory. Do what you will with the parts after that. - d

Comment on Re: read a file in both directions Select or Download Code

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Re^2: (correction) by dynamo (Chaplain) on May 31, 2006 at 12:02 UTC
This was originally a correction note, then I realized that I could just edit the original post to be correct, so I did. I don't see a way to delete this post entirely (short of marking it for consideration, which would be making my mistake into more people's problems), so here's what it was. ---- original content --- oops, `die "no blank lines" unless ($first_blank > 0)` [download] should have been: `die "no blank lines" unless ($first_blank >= 0)` [download]	[reply] [d/l] [select]

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Re^2: (correction)
by dynamo (Chaplain) on May 31, 2006 at 12:02 UTC

---- original content ---

oops,

die "no blank lines" 
  unless ($first_blank > 0)
[download]

die "no blank lines" 
  unless ($first_blank >= 0)
[download]

[reply]
[d/l]
[select]