Re: Syslets, Threadlets, generic AIO support, v6

On Wed, 30 May 2007, Ingo Molnar wrote:

yeah - this is a fundamental design question for Linus i guess :-) glibc
(and other infrastructure libraries) have a fundamental problem: they
cannot (and do not) presently use persistent file descriptors to make
use of kernel functionality, due to ABI side-effects. [applications can
dup into an fd used by glibc, applications can close it - shells close
fds blindly for example, etc.] Today glibc simply cannot open a file
descriptor and keep it open while application code is running due to
these problems.

Here I think we are forgetting that glibc is userspace and there's no
separation between the application code and glibc code. An application
linking to glibc can break glibc in thousand ways, indipendently from fds
or not fds. Like complaining that glibc is broken because printf()
suddendly does not work anymore ;)

#include <stdio.h>
int main(void) {
close(fileno(stdout));
printf("Whiskey Tango Foxtrot?\n");
return 0;
}



- Davide


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