Maintain a conforms_to JSON array on every row for the standards lineage, and a linux_extensions JSON object for glibc-specific behavior. A clearly-labeled extension block renders only when linux_extensions is non-empty. Readers writing portable code see the POSIX baseline first, while Linux-targeted code authors get the extension details inline without searching man pages for ferror or fopencookie.

Yes. A deprecations JSON array on each row holds standard-version pairs noting when a function was deprecated or removed. The page renders a deprecation timeline with the recommended replacement linked. Functions like gets that were removed in C11 carry a clear removal badge so authors do not ship code that fails on modern conforming compilers.

Every row carries a thread_safety field (MT-Safe, MT-Unsafe, async-signal-safe). A badge on each page surfaces the classification, and a thread_safety_notes text column carries the detailed conditions. Readers writing multi-threaded code see at a glance whether they need a mutex. The same field feeds a /posix/functions/mt-safe/ index for filtered browsing.

An optionality field on each row marks the function as Base, XSI, ADV, TIM, or another POSIX option group. A badge surfaces the option group, and a /posix/functions/option/{option}/ index pages every function in that group. Readers writing strictly Base POSIX code filter out XSI-only functions without trial compilation and avoid surprises during conformance audits.

Yes. The errnos array holds the canonical POSIX errno list, and a platform_errnos JSON object keyed by platform overrides per implementation. A conditional list mapping renders platform-specific errno blocks when the data is present. Most functions have a single canonical errno set, but for the handful where it matters, the data is right there.

Each page carries a unique prototype, unique parameter table, unique errno list, unique example code, and unique conformance block. That is more structured data per page than most reference sites publish. Search behavior matches MDN and Microsoft Learn, which rank reliably across thousands of pages because every entry is genuinely unique and ships meaningful per-version updates.

Yes. Maintain a primary_standard field on every row, then expose filter index pages like /posix/functions/standard/posix-1-2024/ or /posix/functions/standard/posix-1-2017/. Readers targeting a specific standards revision pin to the right reference set, and search engines treat each snapshot as a distinct canonical for that standard.

Append the new standard tag to conforms_to on every applicable row, add new function rows for any additions, and flag deprecated rows. The site refreshes on the next sync. The standards-filter index pages regenerate automatically, the conformance badges update everywhere, and editor cost per revision is a JSON diff rather than a 1200-page rewrite of the entire reference set.