[tlbuild] asymptote search path

[Ken Brown]

On 8/11/2009 4:59 PM, John Bowman wrote:
>>     I would have prefered to consistently use ~/.asy too, but Tomek requested
>>     the following change. The rationale is that asy writes to this directory
>>     and ~/.asy might not be writeable (e.g. when using TL from a USB
>>     stick).
>>
>> Ah yes.  I forgot that discussion :(.
>>
>>     We can easily revert this change though (or maybe use some environment
>>     variable to make it optional?). Let me know what you prefer.
>>
>> It seems to me that the unusual case of running asy from USB should not
>> outweigh the advantage of using the common location ~/.asy by default.
>>
>> How about if we have an envvar, say, ASYHOME.  Unset by default.  The
>> code effectively does getenv("ASYHOME") || "~/.asy" to find the location.
> 
> Sure, we can do that.
> 
>> Then our tl-portable script, and/or users running asy from USB, can set
>> the envvar, and the rest of the world doesn't need to worry.

This will also be useful for cygwin users, running the windows version 
of asy, who can set ASYHOME to their cygwin home directory.

Ken