Re: leaks fd for internal functions but not external command

[Chet Ramey]

On 7/23/19 11:20 AM, Sam Liddicott wrote:
> 
> 
> On Tue, 23 Jul 2019 at 16:15, Sam Liddicott <sam@liddicott.com
> <mailto:sam@liddicott.com>> wrote:
> 
> 
> 
>     On Tue, 23 Jul 2019 at 16:13, Chet Ramey <chet.ramey@case.edu
>     <mailto:chet.ramey@case.edu>> wrote:
> 
>         On 7/23/19 11:11 AM, Sam Liddicott wrote:
> 
>         > The report concerns the different behaviour with internal and
>         external
>         > operations.
> 
>         Right. The close-on-exec is deliberate. That's how it was intended.
> 
> 
>     Doesn't close-on-exec usually takes effect only on the process that
>     does the exec?
>     i.e. the fork that does the exec, not the parent process?
> 
> 
> It got closed in the parent. The lsof is running for the parent, the main
> process. /bin/echo has quit before the lsof runs.

You mean case 2 in your original post? That's because redirections are
performed in the child process forked to run /bin/echo, so the fd never
exists in the parent process. I thought you were talking about case 1,
with the builtin echo.

-- 
``The lyf so short, the craft so long to lerne.'' - Chaucer
                 ``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, UTech, CWRU    chet@case.edu    http://tiswww.cwru.edu/~chet/