Re: [PATCH] mktempd: silence dd usage

[Jim Meyering]

Eric Blake wrote:
...
> But the mktempd script requires -p:
>
>   d=`env -u TMPDIR mktemp -d -t -p "$destdir" "$template" 2>/dev/null` \
>
> and FreeBSD mktemp lacks that:
>
> usage: mktemp [-d] [-q] [-t prefix] [-u] templat ...
>        mktemp [-d] [-q] [-u] -t prefix
>
> in other words, since the mktempd usage appears to be hard-coded to GNU
> mktemp, it explains why the FreeBSD mktemp fails the test and we fall
> back to dd.
>
> Since mktemp is not standardized, perhaps we should try multiple
> invocation styles, if we can make BSD's mktemp give us the results we
> want without having to fall back to dd.

I deliberately chose not to do that, to avoid complicating the
implementation.  What would be the motivation for finding a non-GNU
mktemp with adequate semantics when we already have a work-around?
Once you find one, verifying (efficiently) that it does its job safely
and reliably may be quite hard.  If there's a security problem, we should
deal with it regardless.  Performance?  Probably not.