Folders and files

Name		Name	Last commit message	Last commit date
Latest commit History 36 Commits
.github/workflows		.github/workflows
tools		tools
.editorconfig		.editorconfig
.gitattributes		.gitattributes
Dockerfile		Dockerfile
LICENSE		LICENSE
Makefile		Makefile
README.md		README.md
go.mod		go.mod
main.go		main.go
tz.conf		tz.conf

Repository files navigation

`gotwc` - Tiny world clock in Go! 🚀

Fast, CLI world clock that displays time zone information usingtz database to read validtz entries.

$gotwc -h -f tools/samples/tz-small.confAmerica/New_York     2023-12-11 12:37:13America/Los_Angeles  2023-12-11 09:37:13UTC                  2023-12-11 17:37:13Europe/London        2023-12-11 17:37:13Europe/Paris         2023-12-11 18:37:13Asia/Tokyo           2023-12-12 02:37:13Australia/Sydney     2023-12-12 04:37:13

Highlights

🚀Fast -10X times faster thantwc.c and65X timesfaster thandate.¹
Only ≈7 ms for one entry, and ≈177 ms for ≈ 600entries.
🔒Robust - tested to work with alltz database entries,version 2023c.
📦Self-contained - zero dependencies,lightweight (110 lines,2458 bytes).

Getting Started

Prerequisites

If you are buildinggotwc, you'll need:

AGo compiler

Installing

If you haveHomebrew installed, just run:

brew install Neved4/homebrew-tap/gotwc

Alternatively, clone the repository:

git clone https://github.com/Neved4/gotwc

Then build:

go build

Usage

The following usage and options are available:

gotwc [-h] [-f path] [-s format] [-t timezone] ...Options:  -f path      Read config from path (default "$HOME/.config/twc/tz.conf")  -h      Print in human-readable format  -s format      Set desired time format (e.g. "%Y-%m-%d")  -t timezone      specific timezone (e.g. "Asia/Tokyo")Examples:  Print Tokyo's date in a human-readable format with YY-MM-DD format:    $ gotwc -h -s %Y-%m-%d -t Asia/Tokyo    Asia/Tokyo  2024-01-02 15:04:05    Print date in Los Angeles using an environment variable for the timezone:      $ TZ=America/Los_Angeles gotwc    2024-01-02T15:04:05-0800Environment:  XDG_CONFIG_HOME    When defined, it will be used to store the tz.conf file.  TZ    Timezone to use when displaying dates.Files:  ~/.config/twc/tz.conf    Stores tz database entries to be displayed.See also:  environ(7)

Docker

To compile the binary inside aDocker image, run:

docker build.

Compatibility

Runs onLinux,macOS and*BSD systems on bothx86_64 andarm64.

Standards

gotwc should run on mostPOSIX.1-2017² compatible systems andproduceISO 8601³ output.

License

gotwc is licensed under the terms of theMIT License.

See theLICENSE file for details.

Related Projects

oz/tz - awesome cli time zone helper
tzdiff - cli timezone diff
Neved4/twc - tiny world clock in C

Footnotes

cfr.date command takes ≈931 ms when iterating over ≈ 600entries. Measured withhyperfine.↩
IEEE Std 1003.1-2017: Standard for Information Technology— Portable Operating System Interface (POSIX®),
ISO/IEC/IEEE 9945:2009/COR 2:2017. URL:https://pubs.opengroup.org/onlinepubs/9699919799/↩
ISO 8601: Date and time \ — Representations for information interchange, ISO 8601-1:2019.
URL:https://www.iso.org/obp/ui/#iso:std:iso:8601:-2:ed-1:v1:en ↩