Hi Bilahari, >I want to know why there is need for two files lwipopts.h , opts.h. >They look redundant.
opt.h defines what can be configured and a standard option for this. lwipopts.h is for the user to configure the stack. The two file are needed because the options are tested using #if LWIP_XXX, which means they _must_ exist (in contrast to #ifdef). If opt.h was not included, nobody would know all the existing options... >SYS_LIGHTWEIGHT_PROT exactly means ?. Hm, we don't really know that ourselves (the developers)... We were talking about it and thinking about throwing away that option (making =1 the default) >When you say LIGHTWEIGHT port do you mean Operating System presence or no Operating system presence? That doesn't really depen on an OS. In some places, LIGHTWEIGHT=0 means semaphores (and you should have an OS for that), in other places it means no protection at all. Using LIGHTWEIGHT, protection is done by disabeling interrupts. This way, even if you don't have an OS and receive packets in interrupt context, you can protect for example the pbuf or memp pools. In the current implementation, if you have an OS or using interrupts to receive packets (in contrast to polling the ethernet hardware) you MUST set SYS_LIGHTWEIGHT_PROT to 1, or else the pbuf pool can get corrupted. Simon _______________________________________________ lwip-users mailing list [email protected] http://lists.nongnu.org/mailman/listinfo/lwip-users
