On Mon, Mar 6, 2023 at 8:15 PM Rob Landley <r...@landley.net> wrote: > > On 3/6/23 11:43, enh wrote: > > (is there a reason this stuff isn't just `| xargs -P` though? macOS' > > xargs does support -P, as does toybox's. might be worth a comment if > > so.) > > I need to fetch the error return codes to see if any of the parallel build > instances errored out, and the easy way to do that is for them to be shell > jobs > that I query the status of via wait.
ah, right. that makes sense. (at least if you ignore the fact that we can't be the first people to want to run a bunch of jobs _and_ check whether they succeeded or not!) > Xargs -p doesn't stop if any of the commands return error, at least the one in > debian discards stderr entirely, and it's also kinda weird about stdout too? > > $ echo -e 'one\ntwo\nthree\nfour\nfive' | xargs tee /dev/full > $ ls one two three four five > five four one three two > $ echo -e 'one\ntwo\nthree\nfour\nfive' | xargs -P 3 bash -c 'echo $BASHPID; > cat > 2>&1' > 28749 > $ > > The first one created all six (individual) files (with no "/dev/full is full" > complaints), but the second one only output one PID and I didn't dig into why > (at a guess it closed stdout). I could presumably make a toybox version that > did > what I wanted, but then you'd need toybox to build toybox... > > > (and why does scripts/genconfig.sh take so much time if the .config > > file hasn't changed? should genconfig() have a `-nt` test?) > > It has several, but some are commented out because the dependencies are... > awkward. And I erred on the side of being reliable. > > You may remember last time I attacked that: > > http://lists.landley.net/pipermail/toybox-landley.net/2022-June/012906.html > > https://landley.net/notes-2022.html#:~:text=headers%20THREE%20TIMES > > The specific problem for .config has this comment: > > #TODO: "make $SED && make" doesn't regenerate config.h because diff .config > if true #isnewer config.h "$KCONFIG_CONFIG" > > Which expands to "make sed" uses .singleconfig and redoes generated/* from > that, > and then if you do a normal toybox build next and it checks if generated/* is > newer than ".config" the anwser is "yes" so it doesn't rebuild it, which is > wrong. scripts/make.sh doesn't know if KCONFIG_CONFIG changed. yes, incorrect is definitely a lot more annoying than slow (and that one used to bite me a lot). this weekend's changes made things 2x faster on the mac, so that should stop me complaining for at least another year :-) > It needs some design work (probably the same snapshot-the-variables trick > cross > compiler change detection is doing, just add KCONFIG_CONFIG). Hasn't made it > back to the top of the todo pile yet... > > The two hard problems in computer science: naming things, cache invalidation, > and fencepost errors. > > Rob _______________________________________________ Toybox mailing list Toybox@lists.landley.net http://lists.landley.net/listinfo.cgi/toybox-landley.net
