[Toybox] dd and other pending stuff on Android

[enh]

i think this is has come up before, but...

The existing dd is wrong, missing large chunks, and pretty much
untestable (how do you check what ibs and obs are doing when pipes
collate writes so the only way to see the transaction size is under
strace)... I'd throw it out completely but it's one of the commands
Android grabbed out of "pending", and I don't want to break them. --
http://www.landley.net/notes-2017.html#07-07-2017

that's not strictly true. yes, we build dd (and several other things)
from pending:

    toys/pending/dd.c \
    toys/pending/diff.c \
    toys/pending/expr.c \
    toys/pending/getfattr.c \
    toys/pending/gzip.c \
    toys/pending/lsof.c \
    toys/pending/modprobe.c \
    toys/pending/more.c \
    toys/pending/setfattr.c \
    toys/pending/tar.c \
    toys/pending/tr.c \
    toys/pending/traceroute.c \

but we don't have a symlink to dd. so everyone's still using the BSD dd.

we do have symlinks to:

diff
expr
gzip
lsof
modprobe
more
tar
tr

so dd is in the much smaller list of "stuff from pending that folks
need to play simon-says to get at":

dd
getfattr
setfattr
traceroute

break anything in this list, and no-one will notice. it's the
_previous_ list folks will notice. (with the possible exception of
expr, they're not just available, they're actively used.)

-- 
Elliott Hughes - http://who/enh - http://jessies.org/~enh/
Android native code/tools questions? Mail me/drop by/add me as a reviewer.