bc を Homebrew, apk, apt, dnf, MacPorts, Nix, pacman, scoop, zypper でインストール

プロジェクトリンク

• ホームページ
• 上流ドキュメント
• パッケージマネージャページ

コマンドとエイリアス

• bc
• dc

プロジェクトの歴史

The bc language predates GNU bc as a Unix utility for arbitrary-precision arithmetic. POSIX standardizes bc as an arbitrary-precision arithmetic language with an interactive mode, file operands, and the -l math-library option.

GNU bc is the GNU implementation of that utility family. Its documentation describes bc as an arbitrary-precision numeric processing language and ships dc alongside it, keeping the historical relationship between the higher-level bc language and the lower-level desk calculator.

採用の歴史

bc became a portable denominator for shell arithmetic that exceeded the shell's integer facilities or needed decimal scale control. Because POSIX specifies it, distribution packages for bc are common across Unix-like systems, and Homebrew, Debian, Fedora, Arch, Nix, MacPorts, Alpine, and others all carry it.

The GNU package matters especially on systems where the base OS does not include GNU userland behavior by default, such as macOS, and in minimal containers where explicit installation keeps scripts reproducible.

使われ方

Typical command-line use pipes expressions into bc, invokes bc -l for math functions and a nonzero default scale, or runs bc interactively as a tiny programmable calculator. Scripts use it for decimal arithmetic, base conversion, and calculations where shell integer arithmetic is not enough.

The paired dc executable serves users who prefer reverse-polish notation or need the older stack-calculator language.

パッケージ好きにとっての重要性

bc is a package-nerd fossil with live production value: it is tiny, standardized, scriptable, and still frequently pulled into build images because some old configure script, packaging helper, or shell one-liner expects it.

It sits at an interesting boundary between core utility and optional package. On one machine it is part of the assumed Unix furniture; on another it is the missing dependency that breaks a build with a calculator-shaped hole.

タイムライン

• POSIX Issue 7: bc specified as an arbitrary-precision arithmetic language with -l math-library behavior.
• GNU era: GNU bc maintained as the GNU implementation of bc and dc.
• 2020s: bc remains packaged across major Unix-like package managers and used in scripts and build environments.

Related projects

• dc is the older desk-calculator companion shipped by GNU bc.
• POSIX sh arithmetic, awk, Python, and calculator-oriented tools overlap with common bc use cases, but bc remains the small standardized CLI option.
• GNU core-style packaging and Unix userland distributions are the main adoption context.

ソース

• https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html
• https://www.gnu.org/software/bc/
• https://www.gnu.org/software/bc/manual/html_node/bc_toc.html
• source_facts.package-manager