Byte I/O

[Brian]

I'm trying to read a binary file, but the read() function in fstream takes
char*. What I really want are unsigned chars. How can I do this?

Thanks,

--Brian

[Rolf Magnus]

Re: Byte I/O

Brian wrote:
[color=blue]
> I'm trying to read a binary file, but the read() function in fstream
> takes char*. What I really want are unsigned chars. How can I do
> this?[/color]

fstream is just a typedef for basic_fstream<c har>, i.e. a char based
stream. Read() takes a pointer to the stream's template argument type.
So if you create your file as basic_fstream<u nsigned char>, read() will
take an unsigned char*.

[Micah Cowan]

Re: Byte I/O

Rolf Magnus <ramagnus@t-online.de> writes:
[color=blue]
> Brian wrote:
>[color=green]
> > I'm trying to read a binary file, but the read() function in fstream
> > takes char*. What I really want are unsigned chars. How can I do
> > this?[/color]
>
> fstream is just a typedef for basic_fstream<c har>, i.e. a char based
> stream. Read() takes a pointer to the stream's template argument type.
> So if you create your file as basic_fstream<u nsigned char>, read() will
> take an unsigned char*.[/color]

AIUI, you would then also have to define a specialization of
char_traits<> for unsigned char, as that is not defined by the Standard.

Another common practice seems to be to use
reinterpret_cas t<char *>() on a pointer into a buffer of unsigned
char.

--
Micah J. Cowan
micah@cowan.nam e