• Jianlin Lv's avatar
    bpf: Fix compilation warning of selftests · 929e54a9
    Jianlin Lv authored
    Clang compiler version: 12.0.0
    The following warning appears during the selftests/bpf compilation:
    
    prog_tests/send_signal.c:51:3: warning: ignoring return value of ‘write’,
    declared with attribute warn_unused_result [-Wunused-result]
       51 |   write(pipe_c2p[1], buf, 1);
          |   ^~~~~~~~~~~~~~~~~~~~~~~~~~
    prog_tests/send_signal.c:54:3: warning: ignoring return value of ‘read’,
    declared with attribute warn_unused_result [-Wunused-result]
       54 |   read(pipe_p2c[0], buf, 1);
          |   ^~~~~~~~~~~~~~~~~~~~~~~~~
    ......
    
    prog_tests/stacktrace_build_id_nmi.c:13:2: warning: ignoring return value
    of ‘fscanf’,declared with attribute warn_unused_result [-Wunused-resul]
       13 |  fscanf(f, "%llu", &sample_freq);
          |  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    
    test_tcpnotify_user.c:133:2: warning:ignoring return value of ‘system’,
    declared with attribute warn_unused_result [-Wunused-result]
      133 |  system(test_script);
          |  ^~~~~~~~~~~~~~~~~~~
    test_tcpnotify_user.c:138:2: warning:ignoring return value of ‘system’,
    declared with attribute warn_unused_result [-Wunused-result]
      138 |  system(test_script);
          |  ^~~~~~~~~~~~~~~~~~~
    test_tcpnotify_user.c:143:2: warning:ignoring return value of ‘system’,
    declared with attribute warn_unused_result [-Wunused-result]
      143 |  system(test_script);
          |  ^~~~~~~~~~~~~~~~~~~
    
    Add code that fix compilation warning about ignoring return value and
    handles any errors; Check return value of library`s API make the code
    more secure.
    Signed-off-by: default avatarJianlin Lv <Jianlin.Lv@arm.com>
    Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
    Link: https://lore.kernel.org/bpf/20200806104224.95306-1-Jianlin.Lv@arm.com
    929e54a9
test_tcpnotify_user.c 3.74 KB