[PD] Looking for a way to add bytes to beginning of a file using [binfile]

Antonio Roberts antonio at hellocatfood.com
Sat Sep 22 19:02:40 CEST 2012


After some experimenting I solved the problem.

I first add the bytes that I want to add. I then use a second
[binfile] object and use a loop ( [bang( / [until] ) to send each byte
to the other [binfile]. This adds bytes instead of overwriting.

On 22 September 2012 11:41, Jamie Bullock <jamie at postlude.co.uk> wrote:
>
> On 20 Sep 2012, at 17:33, Antonio Roberts <antonio at hellocatfood.com> wrote:
>
>> I'm attempting to use [binfile] to add additional bytes to a file. If
>> I first read the file - using [read(  - and then specify the write
>> position -  [writeat 0 ( - when I add bytes they _overwrite_ the
>> already existing bytes instead of adding new ones.
>>
>> Previously I have used one [binfile] object to read a file output each
>> byte of it to another [binfile] object. This method has worked great
>> for small files but when I'm faced with 60mb files it takes far too
>> long!
>>
>> Is there a way to add bytes to the beginning of a file without overwriting?
>>
>
> DId you solve this in the end?
>
> [binfile] could be trivially extended to allow an |insert( method, which inserts bytes without overwriting. However, I suspect this kind of insert operation is going to be relatively inefficient even if it's done on the C side.
>
> Another option, as I suggested off-list is to use [shell] + "cat", but this isn't portable.
>
> Something else you could explore is using [pdlua] and a bit of Lua script: http://www.lua.org/pil/21.2.2.html
>
> For the sort of work you're doing it wouldn't hurt to incorporate pdlua into your toolbox anyhow.
>
> best,
>
> Jamie
>
>
>



-- 
============================
antonio at hellocatfood.com
http://www.hellocatfood.com
============================



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