diff --git a/sources/tech/20170820 How To Display Date And Time In History Command.md b/translated/tech/20170820 How To Display Date And Time In History Command.md similarity index 63% rename from sources/tech/20170820 How To Display Date And Time In History Command.md rename to translated/tech/20170820 How To Display Date And Time In History Command.md index 52fcaf3742..402b471d92 100644 --- a/sources/tech/20170820 How To Display Date And Time In History Command.md +++ b/translated/tech/20170820 How To Display Date And Time In History Command.md @@ -1,22 +1,19 @@ -translating by lujun9972 -How To Display Date And Time In History Command +让 History 命令显示日期和时间 ====== -We all are familiar with History command. It stores/keep all the commands executed by bash in terminal into `.bash_history` file, which will help us to recheck the previously executed commands by user for further investigation. +我们都对 History 命令很熟悉。它将终端上 bash 执行过的所有命令存储到 `.bash_history` 文件中，来帮助我们复查用户之前执行过的命令。 -By default history command shows only the commands executed by users and it doesn't print the date and time but it logs the time when you ran a command. +默认情况下 history 命令直接显示用户执行的命令而不会输出运行命令时的日期和时间，即使 history 命令记录了这个时间。 -Whenever you run history command, it looks for an environment variable called `HISTTIMEFORMAT`, which tells how to format date & time with history command. +运行 history 命令时，它会检查一个叫做 `HISTTIMEFORMAT` 的环境变量，这个环境变量指明了如何格式化输出 history 命令中记录的这个时间。 -If the value is null or not set then it will shows default results like how most of the systems shows (Without date and time). +若该值为 null 或者根本没有设置，则它跟大多数系统默认显示的一样，不会现实日期和时间。 -HISTTIMEFORMAT takes values from strftime (strftime - convert date and time to a string). When you have date and time in history command output, it might help you to track the issue easily. +`HISTTIMEFORMAT` 使用 strftime 来格式化显示时间 (strftime - 将日期和时间转换为字符串)。history 命令输出日期和时间能够帮你更容易地追踪问题。 - * **%T :** Replaced by the time ( %H : %M : %S ). - * **%F :** Equivalent to %Y - %m - %d (the ISO 8601:2000 standard date format). + * **%T：** 替换为时间 ( %H：%M：%S )。 + * **%F：** 等同于 %Y-%m-%d (ISO 8601：2000 标准日期格式)。 - - -See below default history command output. +下面是 history 命令默认的输出。 ``` # history 1 yum install -y mysql-server mysql-client @@ -52,57 +49,55 @@ See below default history command output. ``` -We can set this environment variable in three ways based on our requirements. +根据需求，有三种不同的方法设置环境变量。 - * Temporarily to current user - * Permanently to current/other user - * Permanently to all users + * 临时设置当前用户的环境变量 + * 永久设置当前/其他用户的环境变量 + * 永久设置所有用户的环境变量 +**注意：** 不要忘了在最后那个单引号前加上空格，否则输出会很混乱的。 +### 方法 -1： -**Note :** Don 't forget to add space before the last single-quotes, otherwise the output would be messy. - -### Method-1 : - -Run the following command to set HISTTIMEFORMAT variable temporarily to current user. This will go away after reboot. +运行下面命令为为当前用户临时设置 HISTTIMEFORMAT 变量。这会一直生效到下次重启。 ``` # export HISTTIMEFORMAT='%F %T ' ``` -### Method-2 : +### 方法 -2： -Append following HISTTIMEFORMAT variable to `.bashrc` or `.bash_profile` file to make it permanent for every user. +将 HISTTIMEFORMAT 变量加到 `.bashrc` 或 `.bash_profile` 文件中，让它永久生效。 ``` # echo 'HISTTIMEFORMAT="%F %T "' >> ~/.bashrc -or +或 # echo 'HISTTIMEFORMAT="%F %T "' >> ~/.bash_profile ``` -Run the following command to to effect the changes made to the file. +运行下面命令来让文件中的修改生效。 ``` # source ~/.bashrc -or +或 # source ~/.bash_profile ``` -### Method-3 : +### 方法 -3： -Append following HISTTIMEFORMAT variable to `/etc/profile` file to make it permanent to all users. +将 HISTTIMEFORMAT 变量加入 `/etc/profile` 文件中，让它对所有用户永久生效。 ``` # echo 'HISTTIMEFORMAT="%F %T "' >> /etc/profile ``` -Run the following command to to effect the changes made to the file. +运行下面命令来让文件中的修改生效。 ``` # source /etc/profile ``` -See the sample output. +输出结果为。 ``` # history 1 2017-08-16 15:30:15 yum install -y mysql-server mysql-client