GNU Gcal is a command-line utility developed by the GNU Project, which is known for creating free and open-source software. The “gcal” utility is part of the GNU Project and is designed to display and calculate calendars from the command line.
Here are some additional details about the “gcal” utility as provided on the GNU Gcal website:
- Calendar Calculation: “Gcal” is capable of calculating various aspects of calendars, such as the dates of holidays, phases of the moon, sunrise and sunset times, and more. This makes it a versatile tool for performing calendar-related calculations and obtaining specific information about dates and times.
- Customizable Output: The utility offers a range of options to customize the output format of calendars. Users can specify the language, select the calendar system, adjust the week numbering scheme, and control the level of detail in the displayed information. This flexibility allows for personalized calendar displays according to individual preferences.
- Multiple Calendar Systems: “Gcal” supports various calendar systems, including the Gregorian, Julian, Hebrew, Islamic, Persian, French Revolutionary, and many others. This makes it suitable for working with different cultural or historical calendars, enabling users to switch between calendar systems as needed.
- Extensibility: The utility provides a scripting language known as “Gcal Language” that allows users to define custom rules and calculations. This feature allows for the creation of custom calendars, events, and holidays, further extending the functionality and adaptability of the “gcal” utility.
- Localization and Internationalization: GNU Gcal aims to be accessible to users around the world. It provides localization support with translations available in multiple languages. This allows users to view calendar information in their preferred language, making it suitable for a global user base.
- Open Source Software: As part of the GNU Project, “gcal” is released under a free software license, which means it is open source and can be freely used, modified, and distributed. This fosters collaboration and community involvement, encouraging contributions from developers and users to enhance the utility.
gcal Command Examples
1. Display calendar for the current month:
# gcal
2. Display calendar for the month of February of the year 2010:
# gcal 2 2010
3. Provide calendar sheet with week numbers:
# gcal --with-week-number
4. Change starting day of week to 1st day of the week (Monday):
# gcal --starting-day=1
5. Display the previous, current and next month surrounding today:
# gcal .