Write a File in Binary?

editi has asked for the wisdom of the Perl Monks concerning the following question:

Hi Monks,
Monks i try to writy a file as a binary
the file should contains a binary values corresponding to character values
i tried the following code
but it is not working
please help me

#!/usr/bin/perl
open FILE, ">123.txt" or die $!;
print pack("b*","a","b","c") or die $!;
close FILE;
[download]

thanks in advance.

Comment on Write a File in Binary? Download Code

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Re: Write a File in Binary? by Adrade (Pilgrim) on Jul 03, 2007 at 17:27 UTC
Hi editi, First, you're not writing to the file... reformat the third line to read `print FILE pack("b*","a","b","c") or die $!;` Additionally, you'll want, after you open FILE, to write `binmode(FILE);` - I dont know if this is necessary on all platforms, but it certainly can't hurt. Best of luck, -Adam -- By a scallop's forelocks!	[reply] [d/l] [select]
Re: Write a File in Binary? by kyle (Abbot) on Jul 03, 2007 at 17:31 UTC
It might help to use binmode. Your print needs to specify what filehandle it's going to print to (`print FILE pack("b","a","b","c")`). If you want to write the bits for the characters, I think `print FILE "a","b","c"` would work just fine, unless I'm missing something. In any case, I think you should have a look at the pack documentation. I don't think `"b"` is the format you want (but I can't tell what format you do want).	[reply] [d/l] [select]
Re: Write a File in Binary? by marto (Cardinal) on Jul 03, 2007 at 17:33 UTC
editi, Read How do I convert between numeric representations/bases/radixes? from perlfaq4 as well as perlpacktut. Martin	[reply]
Re: Write a File in Binary? by Limbic~Region (Chancellor) on Jul 03, 2007 at 17:28 UTC
editi, Since you didn't bother to tell us what didn't work, I can't tell you what's wrong. I can point you to binmode and print as well as suggest you provide more information. Update: Ok, so after posting I realized I was not being very nice nor was I being as helpful as I could be. I was trying to stress how useless "it didn't work" is when asking a question. While I did point to the docs that ultimately would have lead to the answer, Adrade was much kinder and informative. Cheers - L~R	[reply]