xz: Fix comments.
diff --git a/src/xz/file_io.c b/src/xz/file_io.c
index 7895ee0..c52656c 100644
--- a/src/xz/file_io.c
+++ b/src/xz/file_io.c
@@ -393,10 +393,11 @@
#ifdef TUKLIB_DOSLIKE
setmode(STDIN_FILENO, O_BINARY);
#else
- // Try to set stdout to non-blocking mode. It won't work
+ // Try to set stdin to non-blocking mode. It won't work
// e.g. on OpenBSD if stdout is e.g. /dev/null. In such
- // case we proceed as if stdout were non-blocking anyway
- // (in case of /dev/null it will be in practice).
+ // case we proceed as if stdin were non-blocking anyway
+ // (in case of /dev/null it will be in practice). The
+ // same applies to stdout in io_open_dest_real().
stdin_flags = fcntl(STDIN_FILENO, F_GETFL);
if (stdin_flags == -1) {
message_error(_("Error getting the file status flags "
@@ -701,7 +702,10 @@
#ifdef TUKLIB_DOSLIKE
setmode(STDOUT_FILENO, O_BINARY);
#else
- // Set O_NONBLOCK if it isn't already set.
+ // Try to set O_NONBLOCK if it isn't already set.
+ // If it fails, we assume that stdout is non-blocking
+ // in practice. See the comments in io_open_src_real()
+ // for similar situation with stdin.
//
// NOTE: O_APPEND may be unset later in this function
// and it relies on stdout_flags being set here.
