In C, C++, and whatever else, this what you call it when you define a function like so:

void myfunc( char *somearg, int foo );

The actual function code itself might be in another module, another library, or later in the same source file from which you prototyped. Prototyping is typically done in header files (see #include)

C supports "non-strict" prototyping, in which you don't prototype the args, so:

void myfunc( char *somearg, int foo );

becomes:

void myfunc();

However C++ doesn't like this. gcc will support this with the -fno-strict-prototypes flag on a C++ file.

If you try to use a function without prototyping it, and the function isn't earlier in the same source file, then your compiler won't be too happy with you.

Something in the protoype stage is still a prototype and has not yet reached production.

In the protoype stage, it's all about gathering data and gaining experience so that the final product can be made, and made well.

A project that never actually reaches production stage, or that stays in the protoype stage for too long is said to be vaporware.

If the prototype tests certain design assumptions, then it's a POC.

Pro"to*type (?), n. [F., from L. prototypus original, primitive, Gr. , ; first + type, model. See Proto-, and Type]

An original or model after which anything is copied; the pattern of anything to be engraved, or otherwise copied, cast, or the like; a primary form; exemplar; archetype.

They will turn their backs on it, like their great precursor and prototype. Burke.

 

© Webster 1913.