patch 8.0.1749: VMS: 100% CPU use, redefining mch_open() fails commit https://github.com/vim/vim/commit/6537c421bb626ee92a2487a543e6287d33461bd0 Author: Bram Moolenaar <Bram@vim.org> Date: Mon Apr 23 20:46:16 2018 +0200 patch 8.0.1749: VMS: 100% CPU use, redefining mch_open() fails Problem: VMS: 100% CPU use, redefining mch_open() and mch_fopen() fails. Solution: Do not wait indefinitely in RealWaitForChar(). (Neil Rieck) Do not redefine mch_open() and mch_fopen() on VMS. (Zoltan Arpadffy)

--- a/src/os_vms.c
+++ b/src/os_vms.c
@@ -784,7 +784,7 @@ RealWaitForChar(
 	    return 0;
 	} else if (msec < 0) {
 	    /* no time-out; wait on indefinitely */
-	    continue;
+	    return 1; /* fakeout to force a wait in vms_read() */
 	} else {
 	    /* time-out needs to be checked */
 	    status = sys$gettim(&time_curr);