[Gambas-user] Help with SHELL and EXEC

[Kari Laine]

On Sun, Oct 12, 2008 at 4:31 PM, Benoit Minisini <
gambas at ...1...> wrote:

> On dimanche 12 octobre 2008, Doriano Blengino wrote:
> >
> > Tell me what your tests say to you - this is very interesting because I
> > did not try if that book was true or not.
> >
>
> Strange behaviours.
>
> If I replace INPUT OUTPUT by READ WRITE, the process does not write to its
> standard output anymore.
>
> But if I replace the "tr" program by "cat", then READ WRITE works as
> expected.
>
> So there is something different in "tr" that prevents him to work with the
> READ WRITE options.
>
> Moreover, sometimes the first write to the "tr" process fails (with a bad
> file
> descriptor error message).
>
> All that needs some investigation...
>
> To test whether either WRITE or OUTPUT works without READ or INPUT I made a
little filter which stores it input to output file.
Here is the filter
-------
#include <stdio.h>

int main()
{
int character;
int lask;
FILE *nHandle;

printf("program started\n");
nHandle=fopen("/home/kari/output.txt","w");

character = getc(stdin);


        while(character != EOF)
        {
        //printf("%d",character);
        fputc(character,nHandle);
        character = getc(stdin);
        }

close(nHandle);

}
-------------------------

Then I start process like this

nProcess = EXEC ["/home/kari/dblpipe/a.out"] FOR WRITE

I also tried OUTPUT instead of WRITE


Then I have a button with code

PUBLIC SUB Button1_Click()

  WRITE #nProcess, "heippa" & Chr(10)

END

I also tried PRINT instead of WRITE and with or without Chr(10).

I can't get it working - nothing ends up in output.txt file. It could be a
question of buffering somewhere but I don't know.

Hopefully this process handling thing can be fixed (or not if it is a
feature of Linux) because this would be great way to integrate to other
programs.
Every programming language has concept of stdin and stdout as far as I know.

Thank you for all the help so far.

Best Regards
Kari Laine