Add a helper function to match qemu_open() which may return files
under the /dev/fdset prefix. Those shouldn't be removed, since it's
only a qemu namespace.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
 include/qemu/osdep.h |  1 +
 util/osdep.c         | 15 +++++++++++++++
 2 files changed, 16 insertions(+)

diff --git a/include/qemu/osdep.h b/include/qemu/osdep.h
index 0f97d68586..9bd3dcfd13 100644
--- a/include/qemu/osdep.h
+++ b/include/qemu/osdep.h
@@ -462,6 +462,7 @@ int qemu_mprotect_none(void *addr, size_t size);
 
 int qemu_open(const char *name, int flags, ...);
 int qemu_close(int fd);
+int qemu_unlink(const char *name);
 #ifndef _WIN32
 int qemu_dup(int fd);
 #endif
diff --git a/util/osdep.c b/util/osdep.c
index 3f04326040..f7d06050f7 100644
--- a/util/osdep.c
+++ b/util/osdep.c
@@ -370,6 +370,21 @@ int qemu_close(int fd)
     return close(fd);
 }
 
+/*
+ * Delete a file from the filesystem, unless the filename is /dev/fdset/...
+ *
+ * Returns: On success, zero is returned.  On error, -1 is returned,
+ * and errno is set appropriately.
+ */
+int qemu_unlink(const char *name)
+{
+    if (g_str_has_prefix(name, "/dev/fdset/")) {
+        return 0;
+    }
+
+    return unlink(name);
+}
+
 /*
  * A variant of write(2) which handles partial write.
  *
-- 
2.24.0