From 11dc0016bb72372bbd46b964fb57f4d10448225a Mon Sep 17 00:00:00 2001 From: Pádraig Brady Date: Tue, 22 Dec 2009 07:36:12 +0000 Subject: wc: line-buffer the printed counts * src/wc.c (main): Set stdout to line buffered mode to ensure parallel running instances don't intersperse their output. This adds 6.5% to the run time in the worst case of many zero length files, but has neglible impact for standard sized files. * tests/misc/wc-parallel: New test for atomic output. * tests/Makefile.am: Reference it. * NEWS: Mention the fix This is similar to commit 710fe413, 20-10-2009, "md5sum, sha*sum, sum: line-buffer the printed checksums" --- tests/misc/wc-parallel | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) create mode 100755 tests/misc/wc-parallel (limited to 'tests/misc/wc-parallel') diff --git a/tests/misc/wc-parallel b/tests/misc/wc-parallel new file mode 100755 index 000000000..7c74c5518 --- /dev/null +++ b/tests/misc/wc-parallel @@ -0,0 +1,37 @@ +#!/bin/sh +# Ensure that wc prints counts atomically +# so that concurrent processes don't intersperse their output + +# Copyright (C) 2009 Free Software Foundation, Inc. + +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation, either version 3 of the License, or +# (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. + +# You should have received a copy of the GNU General Public License +# along with this program. If not, see . + +. $srcdir/test-lib.sh + +if test "$VERBOSE" = yes; then + set -x + md5sum --version +fi + + +(mkdir tmp && cd tmp && seq 2000 | xargs touch) + +# This will output at least 16KiB per process +# and start 3 processes, with 2 running concurrently, +# which triggers often on Fedora 11 at least. +(find tmp tmp tmp -type f | xargs -n2000 -P2 wc) | +sed -n '/0 0 0 /!p' | +grep . > /dev/null && fail=1 + +Exit $fail -- cgit v1.2.3-54-g00ecf