Avoid using non-portable `echo -n` in tests.

diff --git a/diff.h b/diff.h
index c34688881d7ea80ecbe2ff1b3cca880f6f06f598..a49d865bd9cb0fa5ff27ccad7049074afb0002e9 100644 (file)
--- a/diff.h
+++ b/diff.h
@@ -161,6 +161,8 @@ extern void diff_tree_combined(const unsigned char *sha1, const unsigned char pa
 
 extern void diff_tree_combined_merge(const unsigned char *sha1, int, struct rev_info *);
 
+void diff_set_mnemonic_prefix(struct diff_options *options, const char *a, const char *b);
+
 extern void diff_addremove(struct diff_options *,
                           int addremove,
                           unsigned mode,