bash 是否可以通过 shell 重定向捕获彩色输出？

Can colorized output be captured via shell redirect?

提问by billc

Various bash commands I use -- fancy diffs, build scripts, etc, produce lots of color output.

我使用的各种 bash 命令——花哨的差异、构建脚本等，产生大量的颜色输出。

When I redirect this output to a file, and then cator lessthe file later, the colorization is gone -- presumably b/c the act of redirecting the output stripped out the color codes that tell the terminal to change colors.

当我将此输出重定向到一个文件，然后cat或less稍后的文件时，着色消失了——大概是 b/c 重定向输出的行为剥离了告诉终端改变颜色的颜色代码。

Is there a way to capture colorized output, including the colorization?

有没有办法捕获彩色输出，包括着色？

采纳答案by ataylor

One way to capture colorized output is with the scriptcommand. Running scriptwill start a bash session where all of the raw output is captured to a file (named typescriptby default).

捕获彩色输出的一种方法是使用script命令。运行script将启动一个 bash 会话，其中所有原始输出都被捕获到一个文件中（typescript默认命名）。

回答by Walter Mundt

Redirecting doesn't strip colors, but many commands will detect when they are sending output to a terminal, and will not produce colors by default if not. For example, on Linux ls --color=auto(which is aliased to plain lsin a lot of places) will not produce color codes if outputting to a pipe or file, but ls --colorwill. Many other tools have similar override flags to get them to save colorized output to a file, but it's all specific to the individual tool.

重定向不会去除颜色，但许多命令会检测它们何时将输出发送到终端，如果没有，默认情况下不会产生颜色。例如，在 Linux ls --color=auto（ls在很多地方别名为纯色）如果输出到管道或文件时不会产生颜色代码，但ls --color会产生。许多其他工具都有类似的覆盖标志，可以让它们将彩色输出保存到文件中，但这都是特定于单个工具的。

Even once you have the color codes in a file, to see them you need to use a tool that leaves them intact. lesshas a -rflag to show file data in "raw" mode; this displays color codes. edit:Slightly newer versions also have a -R flag which is specifically aware of color codes and displays them properly, with better support for things like line wrapping/trimming than raw mode because less can tell which things are control codes and which are actually characters going to the screen.

即使您将颜色代码保存在文件中，要查看它们，您也需要使用使它们保持完整的工具。 less有一个-r标志以“原始”模式显示文件数据；这将显示颜色代码。 编辑：较新的版本也有一个 -R 标志，它专门识别颜色代码并正确显示它们，与原始模式相比，对换行/修剪等内容的支持更好，因为更少人可以分辨哪些是控制代码，哪些是实际字符走向屏幕。

回答by geekQ

Inspired by the other answers, I started using script. I had to use -cto get it working though. All other answers, including tee, different scriptexamples did not work for me.

受到其他答案的启发，我开始使用script. 我不得不使用-c它来让它工作。所有其他答案，包括tee不同的script例子对我都不起作用。

Context:

语境：

• Ubuntu 16.04
• running behavior tests with behaveand starting shell command during the test with python's subprocess.check_call()

• Ubuntu 16.04
• behave在使用 python 的测试期间使用和启动 shell 命令运行行为测试subprocess.check_call()

Solution:

解决方案：

script --flush --quiet --return /tmp/ansible-output.txt --command "my-ansible-command"

Explanation for the switches:

开关说明：

• --flushwas needed, because otherwise the output is not well live-observable, coming in big chunks
• --quietsupresses the own output of the script tool
• -c, --commanddirectly provides the command to execute, piping from my command to script did not work for me (no colors)
• --returnto make script propagate the exit code of my command so I know if my command has failed

• --flush是需要的，因为否则输出不能很好地实时观察，大块地出现
• --quiet抑制脚本工具自己的输出
• -c, --command直接提供要执行的命令，从我的命令到脚本的管道对我不起作用（没有颜色）
• --return使脚本传播我的命令的退出代码，以便我知道我的命令是否失败

回答by alvherre

some programs remove colorization when they realize the output is not a TTY (i.e. when you redirect them into another program). You can tell some of those to use color forcefully, and tell the pager to turn on colorization, for example use less -R

当某些程序意识到输出不是 TTY 时（即，当您将它们重定向到另一个程序时），它们会删除着色。您可以告诉其中一些强制使用颜色，并告诉寻呼机打开着色，例如使用less -R

回答by Joels Elf

I found that using scriptto preserve colors when piping to lessdoesn't really work (less is all messed up and on exit, bash is all messed up) because less is interactive. scriptseems to really mess up input coming from stdineven after exiting.

我发现使用script管道来保留颜色less并没有真正起作用（less 全部搞砸了，退出时，bash 全部搞砸了），因为 less 是交互式的。即使在退出之后，script似乎也真的搞砸了来自的输入stdin。

So instead of running:

所以，而不是运行：

script -q /dev/null cargo build | less -R

I redirect /dev/nullto it before piping to less:

我/dev/null在管道减少之前重定向到它：

script -q /dev/null cargo build < /dev/null | less -R

So now scriptdoesn't mess with stdinand gets me exactly what I want. It's the equivalent of command | lessbut it preserves colors while also continuing to read new content appended to the file (other methods I tried wouldn't do that).

所以现在script不要乱来stdin，让我得到我想要的。它相当于command | less但它保留了颜色，同时还继续读取附加到文件的新内容（我尝试过的其他方法不会这样做）。

回答by Richard Wiseman

This questionover on superuser helped me when my other answer(involving tee) didn't work. It involves using unbufferto make the command think it's running from a shell.

当我的其他答案（涉及tee）不起作用时，这个关于超级用户的问题帮助了我。它涉及使用unbuffer使命令认为它是从 shell 运行的。

I installed it using sudo apt install expect tclrather than sudo apt-get install expect-dev.

我使用sudo apt install expect tcl而不是sudo apt-get install expect-dev.

I needed to use this method when redirecting the output of apt, ironically.

apt具有讽刺意味的是，在重定向 的输出时，我需要使用此方法。

回答by Richard Wiseman

I use tee: pipe the command's output to teefilenameand it'll keep the colour. And if you don't want to see the output on the screen (which is what teeis for: showing and redirecting output at the same time) then just send the output of teeto /dev/null:

我使用tee: 将命令的输出通过管道传输到teefilename它，它会保持颜色。如果您不想在屏幕上看到输出（这是tee为了：同时显示和重定向输出），那么只需将输出发送tee到/dev/null：

command| teefilename> /dev/null

command| teefilename> /dev/null