[ECOS] why are stdin, stdout, stderr const?

[Ian Gilmour <ian dot gilmour at ffei dot co dot uk>]

Our system runs a simple monitor which is also used to generate error logs, via a simple redirection of stdout/stderr to a ram file.

i.e.
        // Open a ram file to buffer the stdout and stderr
        // Redirect stdout and stderr to our ram buffer
        if ((m_ramfd = open("/ram/stdout", O_WRONLY)) >= 0) {
            StdoutStream = new Cyg_StdioStream(m_ramfd, Cyg_StdioStream::CYG_STREAM_WRITE, false, false, _IOLBF);
            
            // Preserve existing stdio
            termstdout = stdout;
            termstderr = stderr;
            
            // Redirect to ram buffer
            stdout = (FILE *)StdoutStream;
            stderr = (FILE *)StdoutStream;
        }

The above works fine with rodata located in ram, but fails when I modify the locate script to place all readonly data in flash, because stdin, stdout and stderr are located in rodata.

I can fix it by removing the 'const's from the stdin/stdout/stderr declarations in stdin.cxx, stdout.cxx, and stderr.cxx. 

But why are they there in the first place? 
Or should I be doing this via some other method?


cheers,


Ian


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