Date and Time Concepts

Format Date

Format a fixed Unix timestamp as a UTC date string.

fixed timestamp Use a known timestamp and the `!` UTC prefix so replay does not depend on the machine's local timezone.

Format Date

timestamp
format_date.lua
Replay: real traced execution (multi-file project)
local timestamp = 1704067200
local dateText = os.date("!%Y-%m-%d", timestamp)
print("timestamp=" .. timestamp)
print("dateText=" .. dateText)

local timestamp = 1717200000
local dateText = os.date("!%Y-%m-%d", timestamp)
print("timestamp=" .. timestamp)
print("dateText=" .. dateText)

local timestamp = 1735689600
local dateText = os.date("!%Y-%m-%d", timestamp)
print("timestamp=" .. timestamp)
print("dateText=" .. dateText)

  1. timestamp ← 1704067200, dateText ← 2024-01-01

    1local timestamp→ 1704067200 = 1704067200 --@timestamp=1717200000, 17356896002local dateText→ 2024-01-01 = os.date("!%Y-%m-%d", timestamp1704067200)3print("timestamp=" .. timestamp1704067200)4print("dateText=" .. dateText2024-01-01)
    outputtimestamp=1704067200
dateText=2024-01-01

  1. timestamp ← 1717200000, dateText ← 2024-06-01

    1local timestamp→ 1717200000 = 17172000002local dateText→ 2024-06-01 = os.date("!%Y-%m-%d", timestamp1717200000)3print("timestamp=" .. timestamp1717200000)4print("dateText=" .. dateText2024-06-01)
    outputtimestamp=1717200000
dateText=2024-06-01

  1. timestamp ← 1735689600, dateText ← 2025-01-01

    1local timestamp→ 1735689600 = 17356896002local dateText→ 2025-01-01 = os.date("!%Y-%m-%d", timestamp1735689600)3print("timestamp=" .. timestamp1735689600)4print("dateText=" .. dateText2025-01-01)
    outputtimestamp=1735689600
dateText=2025-01-01