Install ccal with Homebrew, apt, MacPorts, Nix

Project links

• Homepage
• Upstream docs
• Package manager page

Commands and aliases

• ccal
• ccalpdf

Project history

The official 2.5.3 page records development from at least version 1.1 on 1 April 2000 through version 2.5.3 on 4 March 2012. Early changes focused on smoother Chinese font rendering, a cache for years 1950 to 2050, Encapsulated PostScript output improvements, and corrections to lunar-date calculation.

The 2.x series expanded language and output support. Version 2.0 added traditional Chinese support for EPS and HTML table output; version 2.1 added traditional or simplified Chinese character-mode output; version 2.3 added UTF-8 output; version 2.4 added XML mode and a sample XSL file; and version 2.5 adopted updated astronomical formulae and corrections.

The project combines calendar software with astronomy code. The official changelog mentions NOVAS-C updates, NASA-published formulae for Delta T, parameters from the second edition of Jean Meeus's Astronomical Algorithms, and corrections based on DE405 for years between 1645 and 2200.

Adoption history

ccal's adoption is mostly in Unix package collections where a small, self-contained calendar utility is cheap to preserve. Its shape is simple: a C++ command-line program, a man page, printable/web output formats, and no network service.

The official page also offers a web interface with PNG, JPEG, PDF, and picture-calendar generation, but the downloadable program is the durable packaging target. That split is typical of older personal utility projects: the static site documents both a web convenience layer and the CLI that package managers can actually preserve.

How it is used

The official page says ccal writes a Gregorian calendar together with a Chinese calendar to standard output, with usage similar to the Unix `cal` program. It supports simplified and traditional Chinese characters and can emit console, EPS, HTML table, and XML formats for printable calendars or web pages.

The related ccalpdf shell script creates PDF calendars using Ghostscript on Unix and Cygwin. Typical package use is scripting, printing, or generating do-it-yourself web calendars that need Chinese lunisolar calendar annotations without depending on a hosted API.

Why package nerds care

ccal is a compact example of a culturally specific CLI that package managers keep useful long after its release cadence slows. It is not a broad productivity suite; it is a focused executable for Chinese lunisolar calendar presentation and printable output formats.

It is also a reminder to distinguish official upstream distribution from mirrors. The official project surface is a static chinesebay.com page with source archives and documentation, so the repository field should stay null unless an official source-control URL is verified.

Timeline

• 2000-04-01: version 1.1 added higher-resolution Chinese font output and a 1950-2050 year cache.
• 2002-03-24: version 2.0 added traditional Chinese support for EPS and HTML table output.
• 2003-01-29: version 2.2 was released under the GNU General Public License.
• 2003-10-04: version 2.3 added UTF-8 output for traditional or simplified Chinese.
• 2006-03-26: version 2.4 added XML mode and a sample XSL file.
• 2008-07-25: version 2.5 adopted NASA Delta T formulae, updated Meeus parameters, and DE405-based corrections.
• 2012-03-04: version 2.5.3 incorporated NOVAS-C updates and 64-bit portability fixes.

Related projects

• NOVAS-C is incorporated for astronomical calculations.
• NASA Delta T formulae, Jean Meeus's Astronomical Algorithms, and DE405 corrections are cited by the official changelog.
• Ghostscript is used by the ccalpdf helper script.

Sources

• https://ccal.chinesebay.com/ccal/ccal.1
• https://ccal.chinesebay.com/ccal/ccal.htm
• https://formulae.brew.sh/api/formula/ccal.json