Re: simple explanation for order-only prerequisite?

[Nicholas Clark]

I'd describe OOPs as "just like a regular dependency, except that the
timestamp isn't checked. Only whether it exists on the filesystem."

On Sun, Nov 3, 2019 at 7:51 AM Robert P. J. Day <address@hidden>
wrote:

>
>   was asked on friday by a make newbie to explain order-only
> prerequisite (OOP), as he was reading the explanation in the manual
> and was having trouble getting a fix on what it really meant.
>
>   i haven't used one for a while, so i reviewed the section and, AIUI
> (and the way i will try to explain it), an OOP means nothing more
> than, while the prerequisite will be timestamp checked to see if the
> rule needs to be invoked, whether or not that happens is simply not
> taken into account for the processing of *this* target.
>
>   in short, while an OOP will be *processed* as usual, its invocation
> has no further effect. is that a fundamentally simple (and accurate)
> way to describe it? thanks muchly.
>
> rday
>
>