tree-wide: use -EBADF for fd initialization

-1 was used everywhere, but -EBADF or -EBADFD started being used in various
places. Let's make things consistent in the new style.

Note that there are two candidates:
EBADF 9 Bad file descriptor
EBADFD 77 File descriptor in bad state

Since we're initializating the fd, we're just assigning a value that means
"no fd yet", so it's just a bad file descriptor, and the first errno fits
better. If instead we had a valid file descriptor that became invalid because
of some operation or state change, the other errno would fit better.

In some places, initialization is dropped if unnecessary.

1 files changed, 1 insertions, 1 deletions

diff --git a/docs/BLOCK_DEVICE_LOCKING.md b/docs/BLOCK_DEVICE_LOCKING.md
index 862d6f0369..a6e3374bc7 100644
--- a/docs/BLOCK_DEVICE_LOCKING.md
+++ b/docs/BLOCK_DEVICE_LOCKING.md
@@ -213,7 +213,7 @@ int lock_whole_disk_from_devname(const char *devname, int open_flags, int flock_
 
     // take the fd to avoid automatic cleanup
     int ret_fd = fd;
-    fd = -1;
+    fd = -EBADF;
     return ret_fd;
 }