Re: bin/59969: iostat(8) doesn't obey -H 0 option

[Paul Goyette <paul%whooppee.com@localhost>]

Yes, your proposed patch fixes the -H0 issue.  Please commit.


On Sat, 7 Feb 2026, Robert Elz wrote:

>    Date:        Sat,  7 Feb 2026 16:30:01 +0000 (UTC)
>    From:        "paul%whooppee.com@localhost via gnats" <gnats-admin%NetBSD.org@localhost>
>    Message-ID:  <20260207163001.1F4DE1A9242%mollari.NetBSD.org@localhost>
>
>  | 	iostat -H 0 -c 2
>  |
>  | and observe repeated headers.
>
> You can work around that by using LINES instead:
>
> 	LINES=0 iostat -c 2
>
> (though doing it just for 2 output records seems pointless!)

This was just for a minimal-reproducer  -  any value >=2 would work
to show the problem;  also -w would work, but requires ^C to exit.

:-)


> You can also try this patch, I think this should fix it (this also
> makes it kind of obvious what the issue is):
>
> Index: iostat.c
> ===================================================================
> RCS file: /cvsroot/src/usr.sbin/iostat/iostat.c,v
> retrieving revision 1.72
> diff -u -u -4 -r1.72 iostat.c
> --- iostat.c	30 Oct 2023 19:43:33 -0000	1.72
> +++ iostat.c	7 Feb 2026 16:53:47 -0000
> @@ -234,9 +234,10 @@
> 		case 'H':
> 			height = strtol(optarg, &ep, 10);
> 			if (height < 0 || *ep != '\0')
> 				errx(1, "bad height (-H) value.");
> -			height += 2;	/* magic, but needed to be sane */
> +			if (height > 0)
> +				height += 2; /* magic, but needed to be sane */
> 			break;
> #if 0
> 		case 'i':
> 			todo |= SHOW_TOTALS | SHOW_NEW_TOTALS;


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