[joveian]

Sorry, I always forget what they are officially called, which is compound literals. You can do ((struct foo){...}). GCC had a different syntax for this before c99 but the only standard way to do such allocations was in a new block, which doesn't help for a function argument.

Edit: also worth mentioning that some of the early implementations of this were very inefficient so you might see complaints from that time, but this is not an issue with modern compilers.

[chetanahuja]

Thanks for pointing this out. I also tried and failed to find "anonymous data allocations". Although (having just read about them) I fail to see how I'd use your proposed string structure to retro-fit an existing codebase using good old char* strings.

[joveian]

The basic idea is to wrap all use of arrays with wrapper functions or macros that take the structure with length and have those wrappers access the array after performing bounds checking. So you would want to never pass a raw array as a function argument, but before compound literals there was fundamentally no good way to change a string literal to such a structure in a function argument that wouldn't violate other basic programming principles. There are still a variety of implementation choices and it is by no means an easy retrofit, but the result can be entirely reasonable. Interacting with 3rd party and standard library code can be awkward and depends on implementation choices (e.g. '\0' termination or not and the related how much of libc do you rewrite). There have been a number of string libraries over the years making various implementation choices, but no general implementation has become all that popular and it seems like most implementations are project specific.