Re: [PATCH]: fold: flush after each line

[Henner Zeller]

On 5 July 2015 at 12:50, Pádraig Brady <address@hidden> wrote:
> On 05/07/15 19:54, Henner Zeller wrote:
>> The 'fold' utility was not very helpful in streaming contexts as
>> outgoing lines where not sent immediately but whenever the buffer was
>> full.
>>
>> Patch attached.
>
> That would have significant performance impact on the normal case.
> We have support for configuring this at runtime though using stdbuf.
> The following shows that and the performance difference:
>
>   $ time yes 12345 | fold -w5 | head -n1M > /dev/null
>   real  0m0.393s
>   user  0m0.458s
>   sys   0m0.017s
>
>   $ time yes 12345 | stdbuf -oL fold -w5 | head -n1M > /dev/null
>   real  0m1.695s
>   user  0m0.797s
>   sys   0m2.280s
>

I could hide it behind a flag (which I wanted to avoid initially for
less user confusion).
Updated patch attached.

> cheers,
> Pádraig.

fold-linebuffer-with-option.patch
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