Re: Selectively turn on and off kernel configuration options

On 02/07/2014 08:47 AM, Winston Smith wrote:
> Hello,
> 
> My apologies it this has been answered before.
> 
> I am looking for a way to specifically turn on or off a single configuration option from the command line. There is the 'config' make target, but this will go through each and every configuration item. I am looking for something like
> 
> make V=2 O=../linux-3.6.3-build CONFIG_OPTION=y config
> 
> whereby make (or a config program) would then go and switch on or off or modularise all dependent configuration options (or warn if the attempted setting requires another configuration to be changed).
> 
> I see there is scripts/kconfig/merge_config.sh. Is this the right way to go?
> 
> Thanks,
> Winston 		 	   		  --
I don't know of anything in the kernel itself, but a simple ex script
should work, try something like:
ex -s -c "%s/^.*CONFIG_OPTION.*$/CONFIG_OPTION=x/" -c "wq" .config
Replace CONFIG_OPTION with the option you want to set, and x with the
value.  It should work for most of the options, but will have issues
with ones that are found in the name of another option (for example,
setting CONFIG_CMDLINE won't work because there are at least 2 other
options that start with CONFIG_CMDLINE_). It also won't handle
dependencies (you need to run make oldconfig to do that) or options in
optional sub-menus (the sub-menu needs to be already selected in the
config).