Re: Ada way to read/write to character file

[Alfred Hilscher <Alfred.Hilscher@icn.siemens.de>]

Hi Michael,

I think it's because Text_IO is designed for sequential files where it
does not make sense to switch between reading and writing. For what you
want do you should use "Direct_IO" which provides an open mode
"Inout_file". 

e.g. package Com_IO is new Direct_IO (Character); -- hope this works as
intended


Michael Bode wrote:
> 
> Hi,
> 
> I'm wondering if there is an Ada way (i.e. standard package) to read
> and write to a character mode (sequential) file like the COM?:
> resp. /dev/ttyS? interface. Ada.Text_IO has no read/write file mode
> and with GNAT I wasn't able to connect two File_Type variables to the
> same physical file at the same time.
> 
> I want to communicate with a device hanging on the RS232 port. I have
> to write to the device and read the answers. I could of course do it
> like open, write, close, open read, close, open,... But I think this
> is not very elegant. I just finished doing it with the Win32
> resp. POSIX API functions, but I'm still wondering if it could be done
> with some standard Ada package.