Re: [ECOS] sdtin/stdout/stderr redirection

[Jonathan Larmour <jifl at eCosCentric dot com>]

Philippe Vandermersch wrote:
> Jifl.
>
> I liked your proposal because I do not have to deal with C++ but :
>
> 1)
> fclose( stdout ) failed :
> ASSERT FAIL: <4>dlmalloc.cxx[765]do_check_chunk() (cyg_uint8 *)p >= 
> arenabase
> ASSERT FAIL: <4>dlmalloc.cxx [ 765] do_check_chunk() (cyg_uint8 *)p >= 
> arenabase
> TRACE: <4>sched.cxx [ 705] disinherit_priority() }}RETURNING UNSET!
> TRACE: <4>mutex.cxx [ 447] unlock()

Bugger, I forgot about that. fclose() is trying to free stdin, but stdin 
was not allocated off the heap.

> 2)
> If I do not close it and do simply : stdout = fdopen(fd_out , "w" ) 
> seems to succeed but printf does print anything

Ah... my guess is that the default buffering mode is full buffering, not 
line buffering, so you would have to set the buffering mode to _IOLBF with 
setvbuf().

If it's not that I'm afraid I don't know off-hand what it could be. 
fdopen() calles fopen_inner() in fopen.cxx, which calls a constructor just 
like you do below.

> 3)
> To make it work, I had to do this in C++:
>
> Cyg_StdioStream *StdoutStream = new Cyg_StdioStream( fd_out, 
> Cyg_StdioStream::CYG_STREAM_WRITE, false, false, _IOLBF );
> if(StdoutStream == NULL) return( ENOMEM );
> stdout = (FILE *)StdoutStream;
>
> It also works for stdin,stderr.

That's good. Although if you had a moment, it would be nice if you could 
have a quick poke around to see why 2) didn't work, and in particular if 
using setvbuf(stdout, NULL, _IOLBF, BUFSIZ); is all it takes.

Jifl
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