Glibc has BUG with process creation:
https://sourceware.org/bugzilla/show_bug.cgi?id=21386
It doesn't behave well when parent and child are from
different pid namespaces and have the same pid.
Use raw syscall without glibc's asserts as workaround.
Also, use raw syscall for getpid() in tests too,
as these two function go in the pair (glibc's getpid()
relies on glibc's fork()).
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>
e997d34b0c