Print usage information to stderr with line break.

1 files changed, 2 insertions, 2 deletions

diff --git a/src/cgol.c b/src/cgol.c
index b4b95e7..d6b28e3 100644
--- a/src/cgol.c
+++ b/src/cgol.c
@@ -245,6 +245,6 @@ print_cell(int i, int j, bool next)
 void
 usage(const char *invocation)
 {
-	printf("Usage: %s [-w WIDTH] [-h HEIGHT] [-s SEEDPROB] [-r RATE] "
-			"[-n GENERATIONS]", invocation);
+	fprintf(stderr, "Usage: %s [-w WIDTH] [-h HEIGHT] [-s SEEDPROB] [-r RATE] "
+			"[-n GENERATIONS]\n", invocation);
 }