Re: [Qemu-devel] Writing a C library to generate qemu command lines and configuration files

[Paolo Bonzini <pbonzini@redhat.com>]

On 02/05/2017 16:59, Richard W.M. Jones wrote:
>> To answer your question: you have to double comma after '=', or else it
>> terminates the value.  There is no other quoting.
>
> Hmm, is that really right?  It seems to me that any comma must be
> doubled.  For example:
> 
> $ qemu-system-x86_64 -name foo,bar -writeconfig - -hda die
> qemu-system-x86_64: -name foo,bar: Invalid parameter 'bar'

That's because, as you found out, "-name" is not a simple option but a
compound one; "-name foo" is short for "-name guest=foo" (compare
"-device e1000").

The grammar mentioned in util/keyval.c says that you have to double
comma in a value, *and* comma is completely invalid in a key.

If you have '=', you have to double commas after it and cannot use it
before.

If you have no '=' at all, then you have to double comma too.

Paolo

> $ qemu-system-x86_64 -name foo,,bar -writeconfig - -hda die
> # qemu config file
> 
> [name]
>   guest = "foo,bar"