bug#30862: 25.3; Need variant of `make-process' that uses file name handlers

bug#30862: 25.3; Need variant of `make-process' that uses file name handlers

[Philipp]

Most fundamental process-related functions (call-process, start-process)
have variants that take file name handlers into account, except
make-process.  Since make-process is more powerful than start-process,
it should also have a variant that honors file name handlers.  For
example, it could accept another keyword argument ‘:file-handlers’
which, if non-nil, would invoke file name handlers based on
‘default-directory’.



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bug#30862: 25.3; Need variant of `make-process' that uses file name handlers

[Michael Albinus]

Philipp <p.stephani2@gmail.com> writes:

Hi Philipp,

> Most fundamental process-related functions (call-process, start-process)
> have variants that take file name handlers into account, except
> make-process.  Since make-process is more powerful than start-process,
> it should also have a variant that honors file name handlers.  For
> example, it could accept another keyword argument ‘:file-handlers’
> which, if non-nil, would invoke file name handlers based on
> ‘default-directory’.

I don't believe we need an extra keyword. It could be handled like
start-file-process and process-file: if default-directory matches an
entry in file-name-handler-list, the respective handler is called;
otherwise the native implementation is applied.

It is up to the file name handler to decide, whether a fallback to the
native implementation shall be applied.

This is different to the behavior of call-process and start-process;
callees of make-process must be aware that a process on a remote host
could be started.

Best regards, Michael.

bug#30862: 25.3; Need variant of `make-process' that uses file name handlers

[Philipp Stephani]

Am Mi., 21. März 2018 um 13:50 Uhr schrieb Michael Albinus
<michael.albinus@gmx.de>:
>
> Philipp <p.stephani2@gmail.com> writes:
>
> Hi Philipp,
>
> > Most fundamental process-related functions (call-process, start-process)
> > have variants that take file name handlers into account, except
> > make-process.  Since make-process is more powerful than start-process,
> > it should also have a variant that honors file name handlers.  For
> > example, it could accept another keyword argument ‘:file-handlers’
> > which, if non-nil, would invoke file name handlers based on
> > ‘default-directory’.
>
> I don't believe we need an extra keyword. It could be handled like
> start-file-process and process-file: if default-directory matches an
> entry in file-name-handler-list, the respective handler is called;
> otherwise the native implementation is applied.
>
> It is up to the file name handler to decide, whether a fallback to the
> native implementation shall be applied.
>
> This is different to the behavior of call-process and start-process;
> callees of make-process must be aware that a process on a remote host
> could be started.

I don't see why call-process and make-process should behave
differently in this regard. For call-process and start-process the
caller has to explicitly opt in into applying file name handlers (by
calling different functions); presumably because people consider it
too dangerous to accidentally start random processes on remote
machines. Why should make-process be different?

bug#30862: 25.3; Need variant of `make-process' that uses file name handlers

[Michael Albinus]

Philipp Stephani <p.stephani2@gmail.com> writes:

Hi Philipp,

> I don't see why call-process and make-process should behave
> differently in this regard. For call-process and start-process the
> caller has to explicitly opt in into applying file name handlers (by
> calling different functions); presumably because people consider it
> too dangerous to accidentally start random processes on remote
> machines. Why should make-process be different?

In general, file name handlers are invoked silently, w/o the need to
adapt the using packages. `call-process' and `start-process' are
exceptions, because sometimes it isn't desired to invoke a file name
handler, even if `default-directory' is remote. Therefore, the new
functions.

`make-process' fits into this category. Whether a new function to be
applied, or an additional argument, doesn't make a difference. The
latter was not possible for `call-process' and `start-process'.

We have now your patch (thanks!), let's continue this way.

Best regards, Michael.

bug#30862: 25.3; Need variant of `make-process' that uses file name handlers

[Eli Zaretskii]

> From: Michael Albinus <michael.albinus@gmx.de>
> Date: Mon, 17 Dec 2018 09:44:23 +0100
> Cc: 30862@debbugs.gnu.org
> 
> We have now your patch (thanks!), let's continue this way.

Does this mean you are no longer opposed to adding this feature?  Your
original response sounded like you had some fundamental disagreement
with this proposal.

bug#30862: 25.3; Need variant of `make-process' that uses file name handlers

[Michael Albinus]

Eli Zaretskii <eliz@gnu.org> writes:

Hi Eli,

> Does this mean you are no longer opposed to adding this feature?  Your
> original response sounded like you had some fundamental disagreement
> with this proposal.

There was never a "fundamental disagreement" making
`make-network-peocess' file name handler aware. I was not sure whether
we need a new keyword, but since all other people seem to prefer this, I
don't oppose.

See also my answer to Stefan in bug#28691 from October 2017.

Best regards, Michael.