[PATCH bpf-next 1/2] selftests/bpf: fix unused-result warning in snprintf_btf.c

[Alan Maguire]

Daniel reports:

+    system("ping -c 1 127.0.0.1 > /dev/null");

This generates the following new warning when compiling BPF selftests:

  [...]
  EXT-OBJ  [test_progs] cgroup_helpers.o
  EXT-OBJ  [test_progs] trace_helpers.o
  EXT-OBJ  [test_progs] network_helpers.o
  EXT-OBJ  [test_progs] testing_helpers.o
  TEST-OBJ [test_progs] snprintf_btf.test.o
/root/bpf-next/tools/testing/selftests/bpf/prog_tests/snprintf_btf.c: In 
function ‘test_snprintf_btf’:
/root/bpf-next/tools/testing/selftests/bpf/prog_tests/snprintf_btf.c:30:2: 
warning: ignoring return value of ‘system’, declared with attribute 
warn_unused_result [-Wunused-result]
  system("ping -c 1 127.0.0.1 > /dev/null");
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  [...]

Fixes: 076a95f5aff2 ("selftests/bpf: Add bpf_snprintf_btf helper tests")
Reported-by: Daniel Borkmann <dan...@iogearbox.net>
Signed-off-by: Alan Maguire <alan.magu...@oracle.com>
---
 tools/testing/selftests/bpf/prog_tests/snprintf_btf.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/snprintf_btf.c 
b/tools/testing/selftests/bpf/prog_tests/snprintf_btf.c
index 3a8ecf8..3c63a70 100644
--- a/tools/testing/selftests/bpf/prog_tests/snprintf_btf.c
+++ b/tools/testing/selftests/bpf/prog_tests/snprintf_btf.c
@@ -27,7 +27,7 @@ void test_snprintf_btf(void)
                goto cleanup;
 
        /* generate receive event */
-       system("ping -c 1 127.0.0.1 > /dev/null");
+       (void) system("ping -c 1 127.0.0.1 > /dev/null");
 
        if (bss->skip) {
                printf("%s:SKIP:no __builtin_btf_type_id\n", __func__);
-- 
1.8.3.1