[Spice-devel] [PATCH] Attempt to manage redirection in a way similar to Unix

[Frediano Ziglio]

> 
> This patch allows remote-viewer to redirect output/error streams to
> files.
> Also if launched from a console program (for instance from the command
> prompt) you are able to see output from the console where you launch
> the program.
> This allow to launch the program with a syntax like
>   > remote-viewer.exe --debug > log.txt 2>&1
> or simply
>   > remote-viewer.exe --debug
> 
> Signed-off-by: Frediano Ziglio <fziglio at redhat.com>

Why not adding also a --log-file=<filename> option?
I think this is much easier for customers than opening a console
window and type the command with redirection.

Frediano

> ---
>  src/virt-viewer-util.c | 29 ++++++++++++++++++++++-------
>  1 file changed, 22 insertions(+), 7 deletions(-)
> 
> diff --git a/src/virt-viewer-util.c b/src/virt-viewer-util.c
> index aec3b77..aba11eb 100644
> --- a/src/virt-viewer-util.c
> +++ b/src/virt-viewer-util.c
> @@ -302,13 +302,28 @@ void virt_viewer_util_init(const char *appname)
>       */
>      CreateMutexA(0, 0, "VirtViewerMutex");
>  
> -    if (AttachConsole(ATTACH_PARENT_PROCESS) != 0) {
> -        freopen("CONIN$", "r", stdin);
> -        freopen("CONOUT$", "w", stdout);
> -        freopen("CONOUT$", "w", stderr);
> -        dup2(fileno(stdin), STDIN_FILENO);
> -        dup2(fileno(stdout), STDOUT_FILENO);
> -        dup2(fileno(stderr), STDERR_FILENO);
> +    /* Get redirection from parent */
> +    HANDLE out = GetStdHandle(STD_OUTPUT_HANDLE);
> +    HANDLE err = GetStdHandle(STD_ERROR_HANDLE);
> +    if (out == INVALID_HANDLE_VALUE)
> +        out = NULL;
> +    if (err == INVALID_HANDLE_VALUE)
> +        err = NULL;
> +
> +    /*
> +     * If not all output are redirected try to redirect to parent console.
> +     * If parent has no console (for instance as launched from GUI) just
> +     * rely on default (no output).
> +     */
> +    if ((out == NULL || err == NULL) &&
> AttachConsole(ATTACH_PARENT_PROCESS)) {
> +        if (out == NULL) {
> +            freopen("CONOUT$", "w", stdout);
> +            dup2(fileno(stdout), STDOUT_FILENO);
> +        }
> +        if (err == NULL) {
> +            freopen("CONOUT$", "w", stderr);
> +            dup2(fileno(stderr), STDERR_FILENO);
> +        }
>      }
>  #endif
>  
> --
> 2.5.0
> 
>