svn commit: r235005 - head/usr.sbin/pc-sysinstall/backend

[Doug Barton]

On Sat, 5 May 2012, Bruce Evans wrote:

> On Fri, 4 May 2012, Doug Barton wrote:
>
>> On 05/04/2012 11:22 AM, Baptiste Daroussin wrote:
>>>>>>>   fetch -s "${FETCHFILE}" >${SIZEFILE}
>>>>>>>   SIZE="`cat ${SIZEFILE}`"
>>>>>>> -  SIZE="`expr ${SIZE} / 1024`"
>>>>>>> +  SIZE=$((SIZE/1024))
>>>>> 
>>>>> Bug; should be '$SIZE/'
>>> No this is perfectly valid
>> 
>> Yes, that works, but it's not our usual style. However, the point is
>> moot as that whole block should be reduced down to:
>> 
>> SIZE=$(( `fetch -s "${FETCHFILE}"` / 1024 ))
>
> The KNF rule that there shall be spaces around binary operators should
> probably apply in shell expressions too, but I don't like the spaces
> on 1 side of (( and )).  Shell syntax doesn't even allow spaces between
> '$' ((.

The "extra" spaces there are a personal style thing. I do it for 2 
reasons, readability primarily, but also to distinguish arithmetic 
operations from $(command) style.

> The rc.d style seems to be to use backquotes and not use $(cmd), but I
> prefer the opposite except possibly in shell expressions like the above
> so that it is easier to separate the commands from the shell expressions.

Yeah, backticks over $() is also a personal style issue, for no 
particular good reason other than "looks better to me." :)

Doug

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