在bash腳本中創建時間戳變量

本文翻譯自：Create timestamp variable in bash script

I am trying to create a timestamp variable in a shell script to make the logging a little easier. 我正在嘗試在shell腳本中創建一個timestamp變量，以使記錄變得更加容易。 I want to create the variable at the beginning of the script and have it print out the current time whenever I issue echo $timestamp . 我想在腳本的開頭創建變量，並在每次發出echo $timestamp時將其打印出當前時間。 It proving to be more difficult then I thought. 事實證明，這比我想的要困難得多。 Here are some things I've tried: 這是我嘗試過的一些方法：

timestamp="(date +"%T")" echo prints out (date +"%T") timestamp="(date +"%T")" echo輸出(date +"%T")

timestamp="$(date +"%T")" echo prints the time when the variable was initialized. timestamp="$(date +"%T")" echo顯示變量初始化的時間。

Other things I've tried are just slight variations that didn't work any better. 我嘗試過的其他內容只是一些細微的變化，效果並不理想。 Does anyone know how to accomplish what I'm trying to do? 有誰知道我該怎麼做？

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#1樓

參考：https://stackoom.com/question/19bi6/在bash腳本中創建時間戳變量

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#2樓

使用命令替換：

timestamp=$( date +%T )

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#3樓

In order to get the current timestamp and not the time of when a fixed variable is defined, the trick is to use a function and not a variable: 爲了獲得當前時間戳而不是定義固定變量的時間，技巧是使用函數而不是變量：

#!/bin/bash

# Define a timestamp function
timestamp() {
  date +"%T"
}

# do something...
timestamp # print timestamp
# do something else...
timestamp # print another timestamp
# continue...

If you don't like the format given by the %T specifier you can combine the other time conversion specifiers accepted by date . 如果您不喜歡%T說明符給出的格式，則可以結合date接受的其他時間轉換說明符。 For GNU date , you can find the complete list of these specifiers in the official documentation here: https://www.gnu.org/software/coreutils/manual/html_node/Time-conversion-specifiers.html#Time-conversion-specifiers 對於GNU date ，您可以在以下官方文檔中找到這些說明符的完整列表： https : //www.gnu.org/software/coreutils/manual/html_node/Time-conversion-specifiers.html#Time-conversion-specifiers

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#4樓

If you want to get unix timestamp, then you need to use: 如果要獲取unix時間戳，則需要使用：

timestamp=$(date +%s)

%T will give you just the time; %T會給你時間。 same as %H:%M:%S (via http://www.cyberciti.biz/faq/linux-unix-formatting-dates-for-display/ ) 與%H:%M:%S （通過http://www.cyberciti.biz/faq/linux-unix-formatting-dates-for-display/ ）

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#5樓

You can use 您可以使用

timestamp=`date --rfc-3339=seconds`

This delivers in the format 2014-02-01 15:12:35-05:00 此格式爲2014-02-01 15:12:35-05:00

The back-tick ( ` ) characters will cause what is between them to be evaluated and have the result included in the line. 反引號（ ` ）字符將導致對它們之間的內容進行評估，並將結果包括在該行中。 date --help has other options. date --help還有其他選項。

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#6樓

timestamp=$(awk 'BEGIN {srand(); print srand()}')

沒有值的srand在大多數Awk實現中都使用當前時間戳。