Re: [Qemu-devel] Bug#632192: [PATCH] add QEMU_LD_PREFIX environment variable

[Riku Voipio <riku.voipio@iki.fi>]

On Fri, Jul 29, 2011 at 05:21:59PM +0200, Johannes Schauer wrote:
> So if we agree on using environment variables to pass options to
> qemu-user we next need to agree on how to name the options.
 
> The following commandline arguments exist (in order as they are checked
> in linux-user/main.c) and I shortly described and proposed a name for
> the environment variable in the same line.
 
> -d (activate log)             - QEMU_LOG
> -D (logfile)                  - QEMU_LOGFILE
> -E (set target env variabe)   - QEMU_SET_ENV
> -U (unset target env variabe) - QEMU_UNSET_ENV
> -0 (set target argv[0])       - QEMU_ARGV0
> -s (stack size)               - QEMU_STACK_SIZE
> -L (elf interpreter prefix)   - QEMU_LD_PREFIX
> -p (page size)                - QEMU_PAGESIZE
> -g (listen for gdb on port)   - QEMU_GDB
> -r (uname)                    - QEMU_UNAME
> -cpu (cpu model)              - QEMU_CPU
> -B (guest base)               - QEMU_GUEST_BASE
> -R (reserved virtual address) - QEMU_RESERVED_VA
> -drop-ld-preload              - QEMU_DROP_LD_PRELOAD

This is a legacy option that could be removed already. The
-U LD_PRELOAD replaces this option. The only known user of this
option (scratchbox) has migrated -U LD_PRELOAD years ago.

> -singlestep                   - QEMU_SINGLESTEP
> -strace                       - QEMU_STRACE
 
> also, there already is the QEMU_STRACE environment variable which could
> be incorporated into the solution?

Else names look good to me.
 
> the -E and -U options can be specified several times so the environment
> variables should be able to receive a list - maybe in the getsubopt(3)
> style?

getsubopt would mean that passing enviroment variable contents with commas
wouldn't work. Perhaps that would still be an acceptable limitation.

Riku