Re: Avoiding file-based constraints for tmp files (ws Re: [minor] umask 400 causes here-{doc,string} failure)

[L A Walsh]

Eduardo Bustamante wrote:
> On Mon, Mar 12, 2018 at 2:05 PM, L A Walsh <bash@tlinx.org> wrote:
> [...]
>   
> > What would be the downside(s) of such an implementation?
> >     
>
> There's code out there that relies on several properties of regular
> files, one of them for example, that you can seek on them. I recommend
> against any change to here documents and here strings that breaks this
> expectation.
>
>   
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Is relying on HERE-doc implementation something that is portable?  Is it
required by POSIX?  Still a few things to remember...

Complete file-system emulations can be done in tmpfs (memory).
The fact that it is  in memory and not a on-disk file system wouldn't be at
issue -- as the emulation of backing by files could be a separate issue from
whether or not here-docs could use memory by default.

At the very least, I said that the use of memory would be subject to
ENV-var limits.  Couldn't those applications needing intermediate files set
those limits to '1-byte', so they'd always fall back to the (or some) 
current
legacy implementation?