Re: ls -l|head seems to look at all files in directory

[Jim Meyering]

Reuben Thomas wrote:

> On Mon, 25 May 2009, Jim Meyering wrote:
>
>> To do what he wants you have to know that ls -1U is the only
>> way to get one output entry per readdir call.
>>
>> Reuben, you want to do it like this:
>>
>>  ls -1U|head|xargs ls -l
>
> Thanks for the hint about -1, but this doesn't seem to make any
> difference: I run "ls -1U|head" in a directory with lots of files
> (about 10,000) and it pauses for a minute or so before giving me my
> ten lines of output.
>
> If I run the command again, then of course it runs almost instantly,
> so I'm not sure what use the loops are in the tests you give.

That amount of delay suggests you're using an old ext2 or ext3 file system.
What FS type, distro, kernel, and mount options?
They used to have problems with directories containing
about that many entries.