=head1 NAME
-perlfaq5 - Files and Formats ($Revision: 1.12 $, $Date: 2002/03/11 22:25:25 $)
+perlfaq5 - Files and Formats ($Revision: 1.15 $, $Date: 2002/04/12 02:02:05 $)
=head1 DESCRIPTION
open FILE, "<", " file "; # filename is " file "
open FILE, ">", ">file"; # filename is ">file"
-
It may be a lot clearer to use sysopen(), though:
@lines = <INPUT>;
-you should think long and hard about why you need everything loaded
-at once. It's just not a scalable solution. You might also find it
-more fun to use the standard DB_File module's $DB_RECNO bindings,
-which allow you to tie an array to a file so that accessing an element
-the array actually accesses the corresponding line in the file.
+you should think long and hard about why you need everything loaded at
+once. It's just not a scalable solution. You might also find it more
+fun to use the standard Tie::File module, or the DB_File module's
+$DB_RECNO bindings, which allow you to tie an array to a file so that
+accessing an element the array actually accesses the corresponding
+line in the file.
-On very rare occasion, you may have an algorithm that demands that
-the entire file be in memory at once as one scalar. The simplest solution
-to that is
-
- $var = `cat $file`;
-
-Being in scalar context, you get the whole thing. In list context,
-you'd get a list of all the lines:
-
- @lines = `cat $file`;
-
-This tiny but expedient solution is neat, clean, and portable to
-all systems on which decent tools have been installed. For those
-who prefer not to use the toolbox, you can of course read the file
-manually, although this makes for more complicated code.
+You can read the entire filehandle contents into a scalar.
{
local(*INPUT, $/);
$var = do { local $/; <INPUT> };
+For ordinary files you can also use the read function.
+
+ read( INPUT, $var, -s INPUT );
+
+The third argument tests the byte size of the data on the INPUT filehandle
+and reads that many bytes into the buffer $var.
+
=head2 How can I read in a file by paragraphs?
Use the C<$/> variable (see L<perlvar> for details). You can either