Show why umount failed.
Change-Id: Id2b3fbc46b8dfbe2f05637fb35c298915cd5f524
diff --git a/toolbox/umount.c b/toolbox/umount.c
index 6eb8b92..890e870 100644
--- a/toolbox/umount.c
+++ b/toolbox/umount.c
@@ -6,6 +6,7 @@
#include <string.h>
#include <unistd.h>
#include <linux/loop.h>
+#include <errno.h>
#define LOOPDEV_MAXLEN 64
#define LOOP_MAJOR 7
@@ -36,7 +37,7 @@
f = fopen("/proc/mounts", "r");
if (!f) {
- fprintf(stdout, "could not open /proc/mounts\n");
+ fprintf(stdout, "could not open /proc/mounts: %s\n", strerror(errno));
return -1;
}
@@ -66,8 +67,8 @@
}
loop = is_loop_mount(argv[1], loopdev);
- if(umount(argv[1])){
- fprintf(stderr,"failed.\n");
+ if (umount(argv[1])) {
+ fprintf(stderr, "failed: %s\n", strerror(errno));
return 1;
}
@@ -75,11 +76,11 @@
// free the loop device
loop_fd = open(loopdev, O_RDONLY);
if (loop_fd < 0) {
- perror("open loop device failed");
+ fprintf(stderr, "open loop device failed: %s\n", strerror(errno));
return 1;
}
if (ioctl(loop_fd, LOOP_CLR_FD, 0) < 0) {
- perror("ioctl LOOP_CLR_FD failed");
+ fprintf(stderr, "ioctl LOOP_CLR_FD failed: %s\n", strerror(errno));
return 1;
}