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NNTP-Posting-Date: Thu, 29 Aug 2024 07:52:02 +0000
From: Mark Summerfield <mark@qtrac.eu>
Subject: Re: is it possible to point to a slice of an array without malloc or
 VLAs?
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On Wed, 28 Aug 2024 09:13:39 +0100, Phil Ashby wrote:
[snip]
> To answer the specific question, I would use pointer arithmetic,
> provided there is no intention to modify values, ie:
> 
> 	char **slice = argv + config->optind;
> 
> thus slice now points at the appropriate part of argv and can be indexed
> or dereferenced / incremented to access elements.
[snip]

Thank you, that works great. I now do that plus store the slice's size using:
argc - optind

I tried to get the size using

#define ARRAYSIZE(a) (&(a)[1] - (a))

char **folders = argv + optind;
int num_folders = argc - optind;
int size = ARRAYSIZE(folders);
printf("%d %d\n", num_folders, size);

but size was always 1.