Re: [PATCH v2] selftests: splice: Add usage() to splice_read.c

On 8/30/24 23:14, Rong Tao wrote:

From: Rong Tao rongtao@cestc.cn

Give the programmer more help information to inform the program on how to use it.

Signed-off-by: Rong Tao rongtao@cestc.cn

tools/testing/selftests/splice/splice_read.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/splice/splice_read.c b/tools/testing/selftests/splice/splice_read.c index 46dae6a25cfb..73a8bc146f97 100644 --- a/tools/testing/selftests/splice/splice_read.c +++ b/tools/testing/selftests/splice/splice_read.c @@ -9,6 +9,12 @@ #include <sys/types.h> #include <sys/stat.h> +void usage(const char *prog) +{

• fprintf(stderr, "Usage: %s INPUT [BYTES]\n", prog);
• fprintf(stderr, " %s /etc/os-release | cat\n", prog);

How does replacing %s INPUT [BYTES]\n", prog with /etc/os-release | cat\n" do? Also what happens on distros that don't have os-release file?

+}

• int main(int argc, char *argv[]) { int fd;

@@ -16,7 +22,7 @@ int main(int argc, char *argv[]) ssize_t spliced; if (argc < 2) {

• fprintf(stderr, "Usage: %s INPUT [BYTES]\n", argv[0]);
  

• usage(argv[0]);
  

  return EXIT_FAILURE; }

@@ -49,6 +55,7 @@ int main(int argc, char *argv[]) size, SPLICE_F_MOVE); if (spliced < 0) { perror("splice");

• usage(argv[0]);
  

  return EXIT_FAILURE; }

I don't understand how this change helps user.

thanks, -- Shuah