sysrc -- a sysctl(8)-like utility for managing /etc/rc.conf et. al.

Julian Elischer julian at
Sun Oct 10 05:24:17 UTC 2010

  Ah grasshoppers...

/me wonders if anyone will get the full significance of that..

On 10/9/10 3:39 PM, Devin Teske wrote:
> On Oct 9, 2010, at 1:25 PM, Garrett Cooper wrote:
>> Why not just do...
>> if [ "x$rc_conf_files" = x -o "x$varname" = x ]
>> then
>>     return ${FAILURE-1}
>> fi
> I think you'll find (quite pleasantly) that if you intonate the lines...
> 	"rc_conf_files [is non-null] OR return failure"
> 	"varname [is non-null] OR return failure"
> Sounds a lot better/cleaner than the intonation of the suggested replacement:
> 	"if x plus rc_conf_files expands to something that is not equal to x OR x plus the expansion of varname is not x then return failure"

For what it matters, I'v enever found the [ "x$foo" = "x" ] construct 
to be useful.
the quoting seems to work for everything I've ever worked on.
so "officially" I'd express it as:

if [ -n  "$rc_conf_files" -o  -n "$varname" ]

but if I were hacking I'd probably express it as

if [ "$rc_conf_files" != "" ] || [ "$varname" != "" ]

I also sometimes find the use of the (()) operator to be useful.

Now One thing that should be bourne in mind (heh) is that
as there is a 'usual' form of format for perl there is one for sh as 
well so it's not "polite"
to make one's sh code look like perl.  :-)

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