Funny, I used a union once to port code when I found-out zero sized arrays were a gcc thing: /* * SC C Compiler 8.8.4f1 (part of MPW 3.3) does not support

Funny, I used a union once to port code when I found-out zero sized arrays were a gcc thing: /* * SC C Compiler 8.8.4f1 (part of MPW 3.3) does not support zero sized * arrays. I use this 'clever' trick involving the preprocessor that * guarantees everything is aligned appropriately. It is possible with * this that some space will be wasted between the header and the * payload if the a single element of the payload is larger than the * header, but that is not the case here. */ #if 0 struct state { mbhdr_t st_mb; /* Screen 1, Line 1 */ short st_serln; /* Screen 1, Line 2 */ short st_astln; unsigned char st_count; unsigned char st_unit; char st_qs[2]; char st_units; /* Screen 1, Line 3 */ avunit_t st_avms[0]; }; #else struct state { union { struct { mbhdr_t suh_mb; /* Screen 1, Line 1 */ short suh_serln; /* Screen 1, Line 2 */ short suh_astln; unsigned char suh_count; unsigned char suh_unit; char suh_qs[2]; char suh_units; /* Screen 1, Line 3 */ } su_header; avunit_t su_align[1]; } st_union[1]; }; #define st_mb st_union[0].su_header.suh_mb #define st_serln st_union[0].su_header.suh_serln #define st_astln st_union[0].su_header.suh_astln #define st_count st_union[0].su_header.suh_count #define st_unit st_union[0].su_header.suh_unit #define st_qs st_union[0].su_header.suh_qs #define st_units st_union[0].su_header.suh_units #define st_avms st_union[1].su_align #endif