# Wiki Discussion: protocol/1

**URL:** <https://swi-prolog.discourse.group/t/wiki-discussion-protocol-1/676>\
**Category:** Wiki Discussion\
**Created:** [May 20, 2019, 2:57pm UTC](https://swi-prolog.discourse.group/t/wiki-discussion-protocol-1/676 "2019-05-20T14:57:49Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Wiki](https://avatars.discourse-cdn.com/v4/letter/w/e8c25b/32.png) [@Wiki](https://swi-prolog.discourse.group/u/Wiki)\
**Post date:** [May 20, 2019, 2:57pm UTC](https://swi-prolog.discourse.group/t/wiki-discussion-protocol-1/676/1 "2019-05-20T14:57:49Z")

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This is a topic to discuss the wiki

[protocol/1](https://swi-prolog.discourse.group/t/wiki-how-to-protocol-1/675)

This is based on a StackOverflow answer of [mine](https://stackoverflow.com/questions/40086736/how-to-redirect-trace-output-to-a-file/43046698#43046698), so not need for me to give attribution to it.

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**Author:** ![EricGT](https://avatars.discourse-cdn.com/v4/letter/e/f1d935/32.png) [@EricGT](https://swi-prolog.discourse.group/u/EricGT)\
**Post date:** [May 20, 2019, 6:19pm UTC](https://swi-prolog.discourse.group/t/wiki-discussion-protocol-1/676/2 "2019-05-20T18:19:46Z")

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I wrote this for a specific question on StackOverflow but it could use some refinement to make it more general.

Also it was specific to Windows and to make it useful to all should address both Mac OS and Linux users and be tested on such.

Might also benefit from using [setup\_call\_cleanup/3](http://www.swi-prolog.org/pldoc/man?predicate=setup_call_cleanup/3) and turning into a predicate like record/2,

```prolog
record_trace(+File, +Pred).

```

True when `File` can be opened. Put a trace point on all predicates satisfying the predicate specification `Pred`.

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**Author:** ![EricGT](https://avatars.discourse-cdn.com/v4/letter/e/f1d935/32.png) [@EricGT](https://swi-prolog.discourse.group/u/EricGT)\
**Post date:** [May 21, 2019, 6:48pm UTC](https://swi-prolog.discourse.group/t/wiki-discussion-protocol-1/676/3 "2019-05-21T18:48:31Z")

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> [@Protocol/1 (Used to capture screen to file)](https://swi-prolog.discourse.group/t/protocol-1-used-to-capture-screen-to-file/675/2):
>
> Does this expanded documentation belong one level up, at [SWI-Prolog -- Creating a Protocol of the User Interaction](http://www.swi-prolog.org/pldoc/man?section=protocol) ?

You choose. I never thought about it, just made the Wiki to get the ball rolling. Technically I don’t consider that Wiki done as I have some unanswered/unresolved questions above, but if you want to add the link, all the better. 😃

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**Author:** ![abaljeu](https://yyz2.discourse-cdn.com/free1/user_avatar/swi-prolog.discourse.group/abaljeu/32/136_2.png) [@abaljeu](https://swi-prolog.discourse.group/u/abaljeu)\
**Post date:** [May 21, 2019, 6:34pm UTC](https://swi-prolog.discourse.group/t/wiki-discussion-protocol-1/676/4 "2019-05-21T18:34:36Z")

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Does this expanded documentation belong one level up, at [http://www.swi-prolog.org/pldoc/man?section=protocol](http://www.swi-prolog.org/pldoc/man?section=protocol) ?