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

[Pádraig Brady]

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

cheers,
Pádraig.