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)

"Test for benchmarking the RE engine

so small.vim
if !has("reltime") | finish | endif
func! Measure(file, pattern, arg)
	for re in range(3)
	    let sstart=reltime()
	    let cmd=printf("../vim -u NONE -N --cmd ':set re=%d'".
		\ " -c 'call search(\"%s\", \"\", \"\", 10000)' -c ':q!' %s", re, escape(a:pattern, '\\'), empty(a:arg) ? '' : a:arg)
	    call system(cmd. ' '. a:file)
	    $put =printf('file: %s, re: %d, time: %s', a:file, re, reltimestr(reltime(sstart)))
	endfor
endfunc