Am 08.02.19 um 19:03 schrieb Jeff King: > On Fri, Feb 08, 2019 at 12:49:59PM -0500, Randall S. Becker wrote: >> Would you object to something like this: >> >> if [ ! -e /dev/zero ]; then >> # use shred or some other mechanism (still trying to figure out a solution) >> else >> # existing dd >> fi > > That's fine, as long as it's wrapped up in a function in order to keep > the tests readable. > > Though I suspect we may be able to just find a solution that works > everywhere, without having two different implementations. If we know we > need $count bytes for dd, we could probably just generate a file with > that many NULs in it. > > Other cases don't seem to actually care that they're getting NULs, and > are just redirecting stdin from /dev/zero to get an infinite amount of > input. They could probably use "yes" for that. If the data does not have to be a sequence of zero bytes, the alternatives are: * `test-genrandom seed-string $size` for a sequence of reproducible "random" bytes * `printf "%0*d" $size 0` for a sequence of '0' characters. In t5318, the zero bytes do matter, though. -- Hannes