Re: [PATCH] sub-process: print the cmd when a capability is unsupported

> In handshake_capabilities() we use warning() when a capability
> is not supported, so the exit code of the function is 0 and no
> further error is shown. This is a problem because the warning
> message doesn't tell us which subprocess cmd failed.
> 
> On the contrary if we cannot write a packet from this function,
> we use error() and then subprocess_start() outputs:
> 
>     initialization for subprocess '<cmd>' failed
> 
> so we can know which subprocess cmd failed.
> 
> Let's improve the warning() message, so that we can know which
> subprocess cmd failed.
> 
> Signed-off-by: Christian Couder <chriscool@tuxfamily.org>