Change 15415 by jhi@alpha on 2002/03/22 13:30:38
FAQ sync.
Affected files ...
..... //depot/perl/pod/perlfaq3.pod#59 edit
..... //depot/perl/pod/perlfaq5.pod#42 edit
..... //depot/perl/pod/perlfaq6.pod#35 edit
Differences ...
==== //depot/perl/pod/perlfaq3.pod#59 (text) ====
Index: perl/pod/perlfaq3.pod
--- perl/pod/perlfaq3.pod.~1~ Fri Mar 22 06:45:05 2002
+++ perl/pod/perlfaq3.pod Fri Mar 22 06:45:05 2002
@@ -154,7 +154,7 @@
as it were. A more complete example, with comments, can be found at
http://www.cpan.org/authors/id/TOMC/scripts/toms.exrc.gz
-The a2ps http://www-inf.enst.fr/%7Edemaille/a2ps/black+white.ps.gz does
+The a2ps http://www-inf.enst.fr/%7Edemaille/a2ps/black+white.ps does
lots of things related to generating nicely printed output of
documents, as does enscript at http://people.ssh.fi/mtr/genscript/.
==== //depot/perl/pod/perlfaq5.pod#42 (text) ====
Index: perl/pod/perlfaq5.pod
--- perl/pod/perlfaq5.pod.~1~ Fri Mar 22 06:45:05 2002
+++ perl/pod/perlfaq5.pod Fri Mar 22 06:45:05 2002
@@ -1,6 +1,6 @@
=head1 NAME
-perlfaq5 - Files and Formats ($Revision: 1.12 $, $Date: 2002/03/11 22:25:25 $)
+perlfaq5 - Files and Formats ($Revision: 1.13 $, $Date: 2002/03/16 15:37:26 $)
=head1 DESCRIPTION
@@ -496,6 +496,7 @@
open FILE, "<", " file "; # filename is " file "
open FILE, ">", ">file"; # filename is ">file"
+
It may be a lot clearer to use sysopen(), though:
@@ -763,22 +764,8 @@
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`;
+You can read the entire filehandle contents into a scalar.
-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.
-
{
local(*INPUT, $/);
open (INPUT, $file) || die "can't open $file: $!";
@@ -790,6 +777,13 @@
$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
==== //depot/perl/pod/perlfaq6.pod#35 (text) ====
Index: perl/pod/perlfaq6.pod
--- perl/pod/perlfaq6.pod.~1~ Fri Mar 22 06:45:05 2002
+++ perl/pod/perlfaq6.pod Fri Mar 22 06:45:05 2002
@@ -9,7 +9,7 @@
decoding a URL and checking whether something is a number are handled
with regular expressions, but those answers are found elsewhere in
this document (in L<perlfaq9>: ``How do I decode or create those %-encodings
-on the web'' and L<perlfaq4>: ``How do I determine whether a scalar is
+on the web'' and L<perfaq4>: ``How do I determine whether a scalar is
a number/whole/integer/float'', to be precise).
=head2 How can I hope to use regular expressions without creating illegible and
unmaintainable code?
End of Patch.
