//! Rust-only utility (NOT a port — lives outside `src/ported/` by design).
//!
//! Where zshrs names what the HOST libc does that C zsh gets for free by
//! calling it. zsh hands printf conversions to libc `fprintf`
//! (`print_val`, c:Src/builtin.c:4571), so flag combinations the C standard
//! leaves undefined behave however the platform's libc behaves. zshrs
//! formats by hand and has to state the host's answer.
/// Whether libc `printf` pads `%c` / `%s` with ZEROS when given the `0` flag.
/// The BSD/macOS libc does (`printf %04c x` → `000x`); glibc and musl ignore
/// `0` for string conversions and pad with spaces (` x`).