diff --git a/src/diff.c b/src/diff.c
index bc0364c..4896c04 100644
--- a/src/diff.c
+++ b/src/diff.c
@@ -839,7 +839,13 @@
 		    (diff_flags & DIFF_ICASE) ? "-i " : "",
 		    tmp_orig, tmp_new);
 	    append_redir(cmd, p_srr, tmp_diff);
+#ifdef FEAT_AUTOCMD
+	    ++autocmd_block;	/* Avoid ShellCmdPost stuff */
+#endif
 	    (void)call_shell(cmd, SHELL_FILTER|SHELL_SILENT|SHELL_DOOUT);
+#ifdef FEAT_AUTOCMD
+	    --autocmd_block;
+#endif
 	    vim_free(cmd);
 	}
     }
@@ -942,7 +948,13 @@
 		fullname != NULL ? fullname :
 # endif
 		eap->arg);
+#ifdef FEAT_AUTOCMD
+	++autocmd_block;	/* Avoid ShellCmdPost stuff */
+#endif
 	(void)call_shell(buf, SHELL_FILTER | SHELL_COOKED);
+#ifdef FEAT_AUTOCMD
+	--autocmd_block;
+#endif
     }
 
 #ifdef UNIX