Change 13358 by jhi@alpha on 2001/11/29 13:43:40
Subject: DRAFT perlpacktut.pod - minor diffs to v0.1
From: "Wolfgang Laun" <[EMAIL PROTECTED]>
Date: Wed, 28 Nov 2001 20:35:29 +0100
Message-ID: <[EMAIL PROTECTED]>
Affected files ...
.... //depot/perl/pod/perlpacktut.pod#2 edit
Differences ...
==== //depot/perl/pod/perlpacktut.pod#2 (text) ====
Index: perl/pod/perlpacktut.pod
--- perl/pod/perlpacktut.pod.~1~ Thu Nov 29 07:00:05 2001
+++ perl/pod/perlpacktut.pod Thu Nov 29 07:00:05 2001
@@ -370,10 +370,10 @@
you have to import it with C<use Config>.)
signed unsigned byte length in C byte length in Perl
- C<s!> C<S!> sizeof(short) $Config{shortsize}
- C<i!> C<I!> sizeof(int) $Config{intsize}
- C<l!> C<L!> sizeof(long) $Config{longsize}
- C<q!> C<Q!> sizeof(longlong) $Config{longlongsize}
+ s! S! sizeof(short) $Config{shortsize}
+ i! I! sizeof(int) $Config{intsize}
+ l! L! sizeof(long) $Config{longsize}
+ q! Q! sizeof(longlong) $Config{longlongsize}
The C<i!> and C<I!> codes aren't different from C<i> and C<I>; they are
tolerated for completeness' sake.
@@ -666,7 +666,7 @@
This saves us the trouble of inserting the C<length> call, but it is
in C<unpack> where we really score: The value of the length byte marks the
end of the string to be taken from the buffer. Since this combination
-doesn't make sense execpt when the second pack code isn't C<a*>, C<A*>
+doesn't make sense except when the second pack code isn't C<a*>, C<A*>
or C<Z*>, Perl won't let you.
The pack code preceding C</> may be anything that's fit to represent a
@@ -996,10 +996,14 @@
# Prepare argument for the nanosleep system call
my $timespec = pack( 'L!L!', $secs, $nanosecs );
- # A simple memory dump
+For a simple memory dump we unpack some bytes into just as
+many pairs of hex digits, and use C<map> to handle the traditional
+spacing - 16 bytes to a line:
+
my $i;
- map { ++$i % 16 ? "$_ " : "$_\n" }
- unpack( 'H2' x length( $mem ), $mem );
+ print map { ++$i % 16 ? "$_ " : "$_\n" }
+ unpack( 'H2' x length( $mem ), $mem ),
+ length( $mem ) % 16 ? "\n" : '';
=head1 Authors
End of Patch.
