linux/tools/build/feature/test-setns.c

#define _GNU_SOURCE
#include <sched.h>

int main(void)
{
	return setns(0, 0);
}
#undef _GNU_SOURCE
tools build: Add test for setns() And provide an alternative implementation to keep perf building on older distros as we're about to add initial support for namespaces. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Krister Johansen <kjlx@templeofstupid.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-bqdwijunhjlvps1ardykhw1i@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> 2017-07-18 20:15:29 +00:00			`#define _GNU_SOURCE`
			`#include <sched.h>`

			`int main(void)`
			`{`
			`return setns(0, 0);`
			`}`
tools feature: Undef _GNU_SOURCE at the end of feature tests Since we get all the tests in a single .c file for a first test, tools/build/feature/test-all.c, if individual tests set that define and fail to undef it at its end, then it the test-all.c build will fail due to defining _GNU_SOURCE multiple times, getting us to the slow path, so undef it at the end in tests that define it. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Link: https://lkml.kernel.org/n/tip-w6s00jfo1xabgphzczadl59b@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> 2019-02-12 12:56:57 +00:00			`#undef _GNU_SOURCE`