1 http://bugs.gentoo.org/250342
2 http://sources.redhat.com/bugzilla/show_bug.cgi?id=9685
4 we cant assume sock_cloexec and pipe2 are bound together as the former defines
5 are found in glibc only while the latter are a combo of kernel headers and
6 glibc. so if we do a runtime detection of SOCK_CLOEXEC, but pipe2() is a stub
7 inside of glibc, we hit a problem. for example:
14 if (!popen("ls", "r"))
18 getgrnam() will detect that the kernel supports SOCK_CLOEXEC and then set both
19 __have_sock_cloexec and __have_pipe2 to true. but if glibc was built against
20 older kernel headers where __NR_pipe2 does not exist, glibc will have a ENOSYS
21 stub for it. so popen() will always fail as glibc assumes pipe2() works.
23 diff -durN glibc-2.12.1.orig/socket/have_sock_cloexec.c glibc-2.12.1/socket/have_sock_cloexec.c
24 --- glibc-2.12.1.orig/socket/have_sock_cloexec.c 2008-07-25 18:46:23.000000000 +0200
25 +++ glibc-2.12.1/socket/have_sock_cloexec.c 2009-11-13 00:50:15.000000000 +0100
27 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
31 #include <sys/socket.h>
32 #include <kernel-features.h>
34 #if defined SOCK_CLOEXEC && !defined __ASSUME_SOCK_CLOEXEC
35 int __have_sock_cloexec;
38 +#if defined O_CLOEXEC && !defined __ASSUME_PIPE2