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); +} + 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; }