Introduce usagef() that takes a printf-style format

diff --git a/refs.c b/refs.c
index 24865cf5a6c937834b2a98ccd8d80a652ae5541e..808f56bb27b6ece616f400154fe98c9cef12f8ba 100644 (file)
--- a/refs.c
+++ b/refs.c
@@ -972,8 +972,10 @@ static int repack_without_ref(const char *refname)
        if (!found)
                return 0;
        fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
-       if (fd < 0)
+       if (fd < 0) {
+               unable_to_lock_error(git_path("packed-refs"), errno);
                return error("cannot delete '%s' from packed refs", refname);
+       }
 
        for (list = packed_ref_list; list; list = list->next) {
                char line[PATH_MAX + 100];