This reverts commit 7a11c4a8e5.
It is a problem when libc has pipe2() but the kernel is too
old to have pipe2() and thus pipe2() fails. In xz it's pointless
to have a fallback for non-functioning pipe2(); it's better to
avoid pipe2() completely.
Thanks to Michael Fox for the bug report.
The earlier version compiled but didn't actually work
since sysconf(_SC_PHYS_PAGES) always fails (or so I was told).
Thanks to Ole André Vadla Ravnås for the patch and testing.
It tried to use sysctl() on QNX but
- it broke the build because sysctl() needs -lsocket on QNX;
- sysctl() doesn't work for detecting the core count on QNX
even if it compiled.
sysconf() works. An alternative would have been to use
QNX-specific SYSPAGE_ENTRY(num_cpu) from <sys/syspage.h>.
Thanks to Ole André Vadla Ravnås.
In FreeBSD, cpuset_getaffinity() is the preferred way to get
the number of available cores.
Thanks to Rui Paulo for the patch. I edited it slightly, but
hopefully I didn't break anything.
It's a problem at least on OpenBSD which doesn't support
O_NONBLOCK on e.g. /dev/null. I'm not surprised if it's
a problem on other OSes too since this behavior is allowed
in POSIX-1.2008.
The code relying on this behavior was committed in June 2013
and included in 5.1.3alpha released on 2013-10-26. Clearly
the development releases only get limited testing.
Hiding them makes no sense since normally there's no error
when testing the "good" files. With "bad" files errors are
expected and then it makes sense to keep the messages hidden.
Mention the possible "make check" failure on Solaris in the
Solaris-specific section of INSTALL. It was already in
section 4.5 but it is better mention it in the OS-specific
section too.
I know that soname != app version, but I skip AGE=1
in -version-info to make the soname match the liblzma
version anyway. It doesn't hurt anything as long as
it doesn't conflict with library versioning rules.
