diff options
Diffstat (limited to 'build-aux/write-ifchanged')
| -rwxr-xr-x | build-aux/write-ifchanged | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/build-aux/write-ifchanged b/build-aux/write-ifchanged new file mode 100755 index 0000000000..185ceb0039 --- /dev/null +++ b/build-aux/write-ifchanged @@ -0,0 +1,25 @@ +#!/usr/bin/env bash +# Copyright (C) 2015 Luke Shumaker +# +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero 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 Affero General Public License for more details. +# +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. + +outfile=$1 +tmpfile="$(dirname "$outfile")/.tmp${outfile##*/}" + +cat > "$tmpfile" || exit $? +if cmp -s "$tmpfile" "$outfile"; then + rm -f "$tmpfile" || : +else + mv -f "$tmpfile" "$outfile" +fi |