[9fans] 9fans Digest, Vol 98, Issue 15

[Friedrich Psiorz]

The reason seems to be that while creating a variable foo
in rc is immediately reflected to /env/foo, the reverse is
not true. That is, creating a new file under /env/baz does
not update the current rc instance with a new variable $baz
So in this case, putenv is actually writing to /env/foo,
and it would be visible only if you start a new rc
instance. (or just read from the same file.)

Ok, so I got the whole idea wrong, I guess. I thought that $var is
basically just syntactic sugar for `{cat /env/var}, so referencing a
variable would always read from /env ...
I don't really understand how and why this is not the case though, but
I'll try to find out by reading a few more manpages ...

[Lyndon Nerenberg]

Post by Friedrich Psiorz
I don't really understand how and why this is not the case though, but
I'll try to find out by reading a few more manpages ...

rc caches environment variables. It saves a read(2) every time $foo is referenced. Whether that's a win these days is unknown and deserves a bit of research. Or maybe rc could grow a command that flushes the env cache.

--lyndon

[erik quanstrom]

Post by Friedrich Psiorz
Ok, so I got the whole idea wrong, I guess. I thought that $var is
basically just syntactic sugar for `{cat /env/var}, so referencing a
variable would always read from /env ...
I don't really understand how and why this is not the case though, but
I'll try to find out by reading a few more manpages ...

it would then make sense to say $./fu. an idea i first heard
from mike haertel.

- erik