Re: Re: insert zero into binary files ?

Thank for your advices,

But, previously I'm dealing with ASCII files and now binary files. There should be some different here and I did not see any help on my previous cases.

Ok, This is my program :

#!/usr/bin/perl -w

undef $/;
my $file = <>;
my $i   = length($file);
my $zero = (2048000 - $i) x chr(0);

print "$file" . "$zero";
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and the error is :

Argument "" isn't numeric in repeat (x) at ./a.pl line 6, <> chunk 1.
[download]

Could some body help me ?

Comment on Re: Re: insert zero into binary files ? Select or Download Code

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Re: Re: Re: insert zero into binary files ? by castaway (Parson) on Nov 06, 2003 at 08:29 UTC
The error message tells you exactly what is wrong. Look up the 'x' operator in the perlop manpage. You have the arguments the wrong way around, it should be `$str x $number`. And if you're trying to write to the file you're reading from, that's not how to do it, you'll need to open the file read/write, using '+>' in open. The syntax to print to a filehandle is: `print $file $zero` (Yours tries to print the value of the filehandle and $zero to the default filehandle, which is probably STDOUT (the screen). C.	[reply] [d/l] [select]
Re: Re: Re: Re: insert zero into binary files ? by bh_perl (Monk) on Nov 07, 2003 at 08:32 UTC
Castway, Thanks a lot .... you are very very powerfull and your ideas is very very good. I'm really respect on that... 3dan, thanks .... I have solved my problem by referring at your example and castway guide. bh.	[reply]
Re: Re: Re: insert zero into binary files ? by edan (Curate) on Nov 06, 2003 at 08:29 UTC
Hi. I'm really not sure what you want to do, but my best guess is that you have a file, and you want to pad it to a certain length (2048000) with null (zero) bytes. If that's the case, try this totally untested code as a starting point: `my $desired_size = 2048000; my $current_size = -s $file; my $null_bytes = "\x00" x ($desired_size - $current_size); open OUT, ">>", $file or die; print OUT $null_bytes; close OUT;` [download] -- 3dan	[reply] [d/l]
Re: Re: Re: Re: insert zero into binary files ? by hawtin (Prior) on Nov 06, 2003 at 18:41 UTC
I would suggest a slight modification `my $desired_size = 2048000; my $current_size = -s $file; my $null_bytes = "\x00" x ($desired_size - $current_size); open OUT, ">>", $file or die; binmode OUT; # <-- Some OSs need this print OUT $null_bytes; close OUT;` [download]	[reply] [d/l]