Hi Kenny, The code is fairly modular, so I think it should be possible to pull out a subset that has a reasonably small code footprint. However, this is admittedly not a well-traveled path, so you'll be a bit on your own. The maintainers of the C++ implementation (such as myself) mainly use it on big beefy servers, so we haven't had a whole lot of reason to work on optimizing code footprint.
CAPNP_LITE might be a good starting point. Note that that option was not really designed to minimize code footprint, but rather was designed to identify a subset of code that could be compiled on MSVC circa 2013. MSVC has since improved, and is now able to compile the whole codebase. Hence, CAPNP_LITE is a bit vestigial now and may have bitrotted somewhat. But, it definitely does cut out a lot of bulkier parts of the library, which you'd also want to remove in an embedded system. So it might be a good guide. Another option that might be less work would be to use c-capnproto, which I think is more explicitly designed for constrained use cases. -Kenton On Mon, Jun 7, 2021 at 10:52 AM Kenny Koller <kenny.kol...@gmail.com> wrote: > Hi, > > My team and I were hoping to use Cap'n P on our system to pass messages > around via UDP. There is a powerful Linux system running a control system > but the nodes are STM32F7 devices (1 MB flash, 320 kB of RAM, 216 MHz > Cortex-M7 processor) running FreeRTOS with the LWIP networking stack. > > When I tried to build for the embedded system I ran into some errors > related to a dependency on pthreads (in the KJ library I believe). > > I did some searches and saw discussions in this group from 2015-16 that > suggested things like inheriting from MessageBuilder to get around using > malloc or using nanopb instead. > > I don't fully understand what CAPNP_LITE gets me so maybe this would be > helpful. > > What is the thinking today on this topic? > > Thanks, > > Kenny > > -- > You received this message because you are subscribed to the Google Groups > "Cap'n Proto" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to capnproto+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/capnproto/81988491-bcde-4025-b9b8-74f9a06c6eebn%40googlegroups.com > <https://groups.google.com/d/msgid/capnproto/81988491-bcde-4025-b9b8-74f9a06c6eebn%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "Cap'n Proto" group. To unsubscribe from this group and stop receiving emails from it, send an email to capnproto+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/capnproto/CAJouXQ%3DVmRg4_aLQZ-SR4NK89KxryyhHYsKxv%3DpDsGXYjSk%2BMA%40mail.gmail.com.
