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From: Javier Loureiro on 1 Jul 2008 20:33
I use a small library (physfs) to read files inside a zip (or a
directory if I am in debug). It is a simple and typical virtual
filesystem.

but there are some other libraries that request a FILE * as input. So,
is there any way to wrap an array of memory as an standard FILE?

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From: wasti.redl on 2 Jul 2008 02:58
On Jul 2, 1:33 pm, Javier Loureiro <derethors...(a)gmail.com> wrote:
> I use a small library (physfs) to read files inside a zip (or a
> directory if I am in debug). It is a simple and typical virtual
> filesystem.
>
> but there are some other libraries that request a FILE * as input. So,
> is there any way to wrap an array of memory as an standard FILE?

There's no standard way, since FILE is opaque.

There might be platform-specific intrusive ways of doing it, though.
For example, I know that at least one CRT implementation used to
implement the printf family by delegating to a single function taking
a FILE*, so sprintf had to disguise its target buffer as such.

Sebastian


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From: Edward Rosten on 2 Jul 2008 17:32
On Jul 2, 5:33 am, Javier Loureiro <derethors...(a)gmail.com> wrote:
> I use a small library (physfs) to read files inside a zip (or a
> directory if I am in debug). It is a simple and typical virtual
> filesystem.
>
> but there are some other libraries that request a FILE * as input. So,
> is there any way to wrap an array of memory as an standard FILE?

The GNU C library implementation of FILE* allows you to use FILE* in
much the same way as iostreams. Sadle, this is not standard, though.
Of particular interest to you will be the fmemopen function.

-Ed

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From: Maxim Yegorushkin on 7 Jul 2008 00:01
On Jul 2, 12:33 pm, Javier Loureiro <derethors...(a)gmail.com> wrote:

> I use a small library (physfs) to read files inside a zip (or a
> directory if I am in debug). It is a simple and typical virtual
> filesystem.
>
> but there are some other libraries that request a FILE * as input. So,
> is there any way to wrap an array of memory as an standard FILE?

Using memory mapped files it may be possible to pass a shared memory
file descriptor (shm_open()) into fdopen() to get FILE*.

Max




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