Hi, I am very newbie for using the function 'pack', and here I have some questions :
Have you read the documentation for pack?
perldoc -f pack
And unpack?
perldoc -f unpack
Have you read the pack and unpack tutorial?
perldoc perlpacktut
Q1. Can I expect that pack can do this for me ?
- compress a text file in smaller size
You could implement a compression algorithm with pack/unpack, if you really wanted to.
- besize template 'aAuU', anything else tempplate I can use to prepare fix length
data ?
- if yes, but how do I assuming the block size is? In case, if I write a binary
file and I wanna use seek.
You are going to have to explain that in more detail.
Q2. Does the below results of code can be explained ?
my @arr = ('aa', '999', '!!'); my @back = ();
my @p = qw/a A Z b B h H c C s S i I l L n N v V j J f d F p P u U w x X/;
for $x(@p) { eval "\nprint \"$x ->\"; [EMAIL PROTECTED] = unpack \"${x}3${x}3${x}3\", \(pack \"${x}3${x}3${x}3\", [EMAIL PROTECTED]); print \"\<\$_>\" for [EMAIL PROTECTED]; print \"\\n\"; " };
You *DO* *NOT* have to use eval() to do that! The format strings are interpolated just like any other string.
for my $x ( @p ) {
print "$x ->";
my @back = unpack "${x}3${x}3${x}3", pack "${x}3${x}3${x}3", @arr;
print "<$_>" for @back;
print "\n";
}John -- use Perl; program fulfillment
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