test/test-functions: use truncate instead of dd to create testbed image

This avoids unnecessary noise in the stderr logs which dd always produces,
such as:

0+0 records in
0+0 records out
0 bytes copied, 0.000155284 s, 0.0 kB/s

Using truncate should not result in any functional change; the image will
still be created as a sparse file of the size specified.
This commit is contained in:
Dan Streetman 2019-08-13 08:05:06 -04:00 committed by Yu Watanabe
parent 84c49ad197
commit adcc450f46

View file

@ -543,7 +543,7 @@ create_empty_image() {
fi
rm -f "$TESTDIR/rootdisk.img"
# Create the blank file to use as a root filesystem
dd if=/dev/null of="$TESTDIR/rootdisk.img" bs=1M seek="$_size"
truncate -s "${_size}M" "$TESTDIR/rootdisk.img"
LOOPDEV=$(losetup --show -P -f $TESTDIR/rootdisk.img)
[ -b "$LOOPDEV" ] || return 1
echo "LOOPDEV=$LOOPDEV" >> $STATEFILE