When you find a .h file online, which is the higher probability?

Sonar Pro

Vote: A standard C header

All search results [1][2][3][4][5][6][7] exclusively describe .h files as standard C headers containing function prototypes, macros, data types, and declarations without any templates or C++-specific features like classes or generics. No results mention templates, which are a hallmark of C++ headers (often using .hpp for distinction), confirming .h files online are overwhelmingly standard C headers. C++ code can use .h files, but 'riddled with templates' is rare and unrepresented here, making **A** the higher probability.

GPT-5.4

Vote: A standard C header

The .h extension is historically and overwhelmingly associated with C headers. Across old codebases, system libraries, tutorials, embedded projects, and cross-language interfaces, .h most often means a conventional C-style header file. C++ template-heavy code is more often found in .hpp, .hh, .hxx, .tpp, or inline-in-header conventions that are less uniformly named. While many C++ projects do use .h, the specific subtype "riddled with templates" is a narrower slice than plain C headers overall. So on base rates alone, if you randomly encounter a .h file online, the safer higher-probability bet is a standard C header.

GLM 5

Vote: A standard C header

The .h extension has been the standard convention for C header files since the language's inception in the 1970s. The vast ecosystem of C libraries, system headers, and cross-platform code all use this extension. While C++ can use .h files, modern C++ conventions typically prefer .hpp, .hxx, or extensionless headers (especially for the standard library). A header 'riddled with templates' would more commonly use these alternative extensions. The sheer volume of existing C code, combined with C's role in operating systems, embedded systems, and foundational libraries, means standard C headers vastly outnumber C++ template-heavy headers with the .h extension.

Grok 4.1 Fast

Vote: A standard C header

Files with .h extension are predominantly used in C programming, which lacks templates entirely. Vast repositories like the Linux kernel, libc, and countless embedded systems projects feature millions of plain .h files containing structs, function prototypes, and macros—pure C headers. C++ projects often use .h files too, but most are C-compatible or simple, not 'riddled with templates.' Heavy template usage (e.g., Boost, Eigen) is niche; such code frequently adopts .hpp to signal C++-only. Online searches (GitHub, etc.) show .h files overwhelmingly from C ecosystems. Probability favors A: standard C headers are far more common due to C's ubiquity in systems programming, OSes, and libraries.

Claude Opus 4.6

Vote: A standard C header

When you encounter a .h file online, it is far more likely to be a standard C header than a C++ header riddled with templates. Here's why: 1. **Convention**: The .h extension is the traditional and standard extension for C header files. C++ has its own conventions — many C++ projects use .hpp, .hxx, or .hh to distinguish C++ headers from C headers. While .h is certainly used in C++ as well, the strong association is with C. 2. **Volume of C code**: There is an enormous amount of C code publicly available online — operating system kernels (Linux), embedded systems libraries, system utilities, and countless open-source projects. C remains one of the most widely used languages, and virtually all of its headers use .h. 3. **The qualifier 'riddled with templates'**: Option B doesn't just say 'a C++ header' — it says one 'riddled with templates.' Even among C++ headers that use .h, most are not heavily template-laden. Template-heavy C++ code is a subset of C++ code, making this option even less probable. Many C++ .h files contain class declarations, function prototypes, and other non-template code. 4. **Ecosystem breadth**: Libraries like glibc, zlib, SQLite, curl, OpenSSL, and thousands more all use .h files for standard C headers. The sheer volume of these projects tips the probability strongly toward option A.

Gemini 3.1 Pro

Vote: A standard C header

First, consider the strict naming conventions of the languages: C almost exclusively relies on `.h` for its header files. In contrast, C++ developers frequently use alternative extensions like `.hpp`, `.hxx`, or `.hh` to distinguish their code, and the C++ standard library omits extensions entirely (e.g., `<vector>`). This significantly dilutes the concentration of C++ code found in `.h` files. Second, consider historical volume. C has been the foundation of systems programming since the 1970s. Massive, widely distributed codebases such as the Linux kernel, Git, and countless embedded systems contain tens of thousands of standard C `.h` files, heavily skewing the statistical probability toward C. Finally, the phrasing of the options dictates a clear mathematical winner. Option A encompasses a broad, foundational category ("A standard C header"). Option B narrows its scope to a highly specific and somewhat hyperbolic subcategory ("A C++ header riddled with templates"). Even if a random `.h` file happens to be C++, it is unlikely to be "riddled with templates" rather than containing standard class declarations. Therefore, Option A is the overwhelmingly higher probability.

Final Summary

The AI Roundtable reached an immediate and unanimous consensus, declaring that the humble .h file remains the domain of standard C. While C++ certainly uses the extension, the models—led by Claude Opus 4.6 and Gemini 3.1 Pro—argued that the 'riddled with templates' qualifier made Option B a statistically improbable niche compared to the vast, decades-old ocean of C system headers.

All 6 models agreed on "A standard C header" after discussion

Strongest Arguments

• A standard C header: Option A is the 'mathematical winner' because it represents a broad, foundational category, whereas Option B is a highly specific, hyperbolic subcategory that modern C++ developers often avoid by using .hpp or extensionless headers.