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* Nulls in scalar parameters
@ 2022-10-21  4:50 Clinton Bunch
  2022-10-21 10:33 ` Roman Perepelitsa
  0 siblings, 1 reply; 2+ messages in thread
From: Clinton Bunch @ 2022-10-21  4:50 UTC (permalink / raw)
  To: zsh-workers

I'm working on a zsh/random module and I'm creating a builtin that 
returns a user-specified number of random bytes and either prints it or 
returns it in a parameter.  There exists a small possibility of embedded 
nulls in the output, and I'm not sure how to handle setting such a value 
in a parameter.

One solution is to make it return a hex string, but I'm not sure of the 
utility of such a result.

Metafy looks like it would handle the null problem, but I'm not sure 
what else it does nor how that would play out if printed to a file.

P.S. to be clear, this module would return random data drawn from the 
kernel's entropy pool, rather than a predictable pseudo-random generator 
like rand or erand48



^ permalink raw reply	[flat|nested] 2+ messages in thread

* Re: Nulls in scalar parameters
  2022-10-21  4:50 Nulls in scalar parameters Clinton Bunch
@ 2022-10-21 10:33 ` Roman Perepelitsa
  0 siblings, 0 replies; 2+ messages in thread
From: Roman Perepelitsa @ 2022-10-21 10:33 UTC (permalink / raw)
  To: Clinton Bunch; +Cc: zsh-workers

On Fri, Oct 21, 2022 at 6:51 AM Clinton Bunch <cdb_zsh@zentaur.org> wrote:
>
> I'm working on a zsh/random module and I'm creating a builtin that
> returns a user-specified number of random bytes and either prints it or
> returns it in a parameter.  There exists a small possibility of embedded
> nulls in the output, and I'm not sure how to handle setting such a value
> in a parameter.

This is how bin_sysread does it in system.c.

    setsparam(outvar, metafy(inbuf, count, META_DUP));

`outvar` points to the name of the parameter (e.g., "REPLY"). `inbuf`
points data and `count` is the number of bytes in it.

Roman.


^ permalink raw reply	[flat|nested] 2+ messages in thread

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2022-10-21  4:50 Nulls in scalar parameters Clinton Bunch
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