The WG14 charter for C23 added one principle to the ones in previous standards: [ 15. Application Programming Interfaces (APIs) should be self-documenting when possible. In particular, the order of parameters in function declarations should be arranged such that the size of an array appears before the array. The purpose is to allow Variable-Length Array (VLA) notation to be used. This not only makes the code's purpose clearer to human readers, but also makes static analysis easier. Any new APIs added to the Standard should take this into consideration. ] ISO C doesn't allow using VLA syntax when the parameter used for the size of the array is declared _after_ the parameter that is a VLa. That's a minor issue that could be easily changed in the language without backwards-compatibility issues, and in fact it seems to have been proposed, and not yet discarded, even if it's not going to change in C23. Since the manual pages SYNOPSIS are not bounded by strict C legal syntax, but we already use some "tricks" to try to convey the most information to the reader even if it might not be the most legal syntax, we can also make a small compromise in this case, using illegal syntax (at least not yet legalized) to add important information to the function prototypes. If we're lucky, compiler authors, and maybe even WG14 members, may be satisfied by the syntax used in these manual pages, and may decide to implement this feature to the language. It seems to me a sound syntax that isn't ambiguous, even if it deviates from the common pattern in C that declarations _always_ come before use. But it's a reasonable tradeoff. This change will make the contract between the programmer and the implementation clearer just by reading a prototype. For example, size_t strlcpy(char *restrict dst, const char *restrict src, size_t size); vs size_t strlcpy(char dst[restrict .size], const char *restrict src, size_t size); the second prototype above makes it clear that the 'dst' buffer will be safe from overflow, but the 'src' one clearly needs to be NUL-terminated, or it might cause UB, since nothing tells the function how long it is. Link: <https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2611.htm> Cc: Ingo Schwarze <schwarze@openbsd.org> Cc: JeanHeyd Meneide <wg14@soasis.org> Cc: Martin Uecker <uecker@tugraz.at> Cc: <gcc@gcc.gnu.org> Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com>