in reply to Definitive guide to pack/unpack?

i'm trying to use unpack to read what is essentially a memory dump of several c variables, and i think perhaps i've overestimated the power of unpack...how far off am I? 
# should unpack to:
#   an int32 (4 byte) value of -1
#   a char (1 byte) value of 'A'
#   a null-terminated string value of "ANOTHER"
#   a null-terminated string value of "CSTRING"
$packed_string = "\xFF\xFF\xFF\xFF"
               . "\x41"
               . "\x41\x4e\x4f\x54\x48\x45\x52\x00"
               . "\x43\x53\x54\x52\x49\x4e\x47\x00";

# should just be able to plug in some kind of
# format for unpack, right?
($int,$char,$another,$cstring)
  = unpack('',$packed_string );

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would i instead have to put together subs like get_int(), get_char(), and get_cstring(), calling each of them in the order needed? if so, could I still use pack to make life easier?

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Re^2: Definitive guide to pack/unpack?
by BrowserUk (Patriarch) on Apr 10, 2007 at 21:19 UTC

    What problem are you encountering? 

    #! perl -slw
use strict;
# should unpack to:
#   an int32 (4 byte) value of -1
#   a char (1 byte) value of 'A'
#   a null-terminated string value of "ANOTHER"
#   a null-terminated string value of "CSTRING"
my $packed_string = "\xFF\xFF\xFF\xFF"
               . "\x41"
               . "\x41\x4e\x4f\x54\x48\x45\x52\x00"
               . "\x43\x53\x54\x52\x49\x4e\x47\x00";

# should just be able to plug in some kind of
# format for unpack, right?
my ($int,$char,$another,$cstring)  = unpack('l A1 Z* Z*',$packed_strin
+g );

print "int: $int Char:$char String:$another String:$cstring";

__END__
c:\test>junk7
int: -1 Char:A String:ANOTHER String:CSTRING

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