unpack knows how to deal efficiently with little/big-endian unsigned shorts without you having to do the byte-swapping yourself.
In recent perl's there are actually two mechanisms:
- Little-endian: formats 'v' or 'S<'
- Big-endian: formats 'n' or 'S>'
It's also worth noting that it is far more efficient to use a quantity specifier (number or * after the template character), than to step through the string picking out the individual words yourself.
This demonstrates both template options and both quantity specifiers options. (either could be used with either):
#! perl -slw
use strict;
my $raw = "\x45\xd2\xff\x76\x89\x3a\x00\x33";
my @leUShorts = unpack 'v4', $raw;
print "@leUShorts";
my @leUShorts2 = unpack 'S<*', $raw;
print "@leUShorts2";
my @beUShorts = unpack 'n4', $raw;
print "@beUShorts";
my @beUShorts2 = unpack 'S>*', $raw;
print "@beUShorts2";
__END__
C:\test>junk67
53829 30463 14985 13056
53829 30463 14985 13056
17874 65398 35130 51
17874 65398 35130 51
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
Read Where should I post X? if you're not absolutely sure you're posting in the right place.
Please read these before you post! —
Posts may use any of the Perl Monks Approved HTML tags:
- a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
| |
For: |
|
Use: |
| & | | & |
| < | | < |
| > | | > |
| [ | | [ |
| ] | | ] |
Link using PerlMonks shortcuts! What shortcuts can I use for linking?
See Writeup Formatting Tips and other pages linked from there for more info.