alsactl: fix error handling in check_control_cdev()

Closes: https://github.com/alsa-project/alsa-utils/pull/310
Signed-off-by: qaqland <anguoli@uniontech.com>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>

diff --git a/alsactl/monitor.c b/alsactl/monitor.c
index 36e9398a4943668756676219c32cfd78c80bede3..e830ba56db82e37c930d9bfdc51d4c12baf8fa0d 100644 (file)
--- a/alsactl/monitor.c
+++ b/alsactl/monitor.c
@@ -176,7 +176,7 @@ static int check_control_cdev(int infd, bool *retry)
                ssize_t len = read(infd, buf, sizeof(*ev) + NAME_MAX);
                if (len < 0) {
                        if (errno != EAGAIN)
-                               err = errno;
+                               err = -errno;
                        break;
                } else if (len == 0) {
                        break;