bash 如何 base64 编码 /dev/random 或 /dev/urandom？
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/1250144/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
How to base64 encode /dev/random or /dev/urandom?
提问by alexanderpas
cat /dev/urandomis always a fun way to create scrolling characters on your display, but produces too many non-printable characters.
cat /dev/urandom在显示器上创建滚动字符总是一种有趣的方式，但会产生太多不可打印的字符。
Is there an easy way to encode it on the command-line in such a way that all of its output are readable characters, base64 or uuencode for example.
是否有一种简单的方法可以在命令行上对其进行编码，使其所有输出都是可读字符，例如 base64 或 uuencode。
Note that I prefer solutions that require no additional files to be created.
请注意，我更喜欢不需要创建额外文件的解决方案。
回答by Pascal MARTIN
What about something like
怎么样的东西
cat /dev/urandom | base64
Which gives (lots of) stuff like
这给出了（很多）类似的东西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, without the (useless) cat+pipe :
或者，没有（无用的） cat+pipe ：
base64 /dev/urandom
(Same kind of output ^^ )
（同种输出^^）
EDIT :you can also user the --wrapoption of base64, to avoid having "short lines" :
编辑：您还可以--wrap选择base64, 以避免出现“短线”：
base64 --wrap=0 /dev/urandom
This will remove wrapping, and you'll get "full-screen" display ^^
这将删除包装，您将获得“全屏”显示^^
回答by Adam Batkin
A number of folks have suggested catting and piping through base64or uuencode. One issue with this is that you can't control how much data to read (it will continue forever, or until you hit ctrl+c). Another possibility is to use the ddcommand, which will let you specify how much data to read before exiting. For example, to read 1kb:
许多人建议cat使用base64或uuencode。这样做的一个问题是您无法控制要读取的数据量（它将永远持续下去，或者直到您按 ctrl+c 为止）。另一种可能性是使用该dd命令，它可以让您指定退出前要读取的数据量。例如，读取 1kb：
dd if=/dev/urandom bs=1k count=1 2>/dev/null | base64
Another option is to pipe to the stringscommand which may give more variety in its output (non-printable characters are discarded, any runs of least 4 printable characters [by default] are displayed). The problem with stringsis that it displays each "run" on its own line.
另一种选择是通过管道传递给strings命令，这可能会在其输出中提供更多变化（不可打印的字符被丢弃，任何至少 4 个可打印字符的运行[默认] 都会显示）。问题strings在于它在自己的行上显示每个“运行”。
dd if=/dev/urandom bs=1k count=1 2>/dev/null | strings
(of course you can replace the entire command with
（当然，您可以将整个命令替换为
strings /dev/urandom
if you don't want it to ever stop).
如果你不想让它停止）。
If you want something really funky, try one of:
如果您想要一些非常时髦的东西，请尝试以下之一：
cat -v /dev/urandom
dd if=/dev/urandom bs=1k count=1 2>/dev/null | cat -v
回答by dmckee --- ex-moderator kitten
So, what is wrong with
那么，有什么问题
cat /dev/urandom | uuencode -
?
?
Fixed after the first attempt didn't actually work... ::sigh::
在第一次尝试后修复并没有实际工作...... ::sigh::
BTW-- Many unix utilities use '-' in place of a filename to mean "use the standard input".
顺便说一句——许多 unix 实用程序使用“-”代替文件名来表示“使用标准输入”。
回答by Aaron J Lang
There are already several good answers on how to base64 encode random data (i.e. cat /dev/urandom | base64). However in the body of your question you elaborate:
关于如何对随机数据进行 base64 编码（即cat /dev/urandom | base64），已经有几个很好的答案。但是，在您的问题正文中，您详细说明了：
... encode [urandom] on the command-line in such a way that all of it's output are readable characters, base64 or uuencode for example.
...在命令行上对 [urandom] 进行编码，使其所有输出都是可读字符，例如 base64 或 uuencode。
Given that you don't actually require parseable base64 and just want it to be readable, I'd suggest
鉴于您实际上并不需要可解析的 base64 并且只希望它可读，我建议
cat /dev/urandom | tr -dC '[:graph:]'
base64only outputs alphanumeric characters and two symbols (+ and / by default). [:graph:]will match any printable non-whitespace ascii, including many symbols/punctuation-marks that base64 lacks. Therefore using tr -dC '[:graph:]'will result in a more random-looking output, and have better input/output efficiency.
base64仅输出字母数字字符和两个符号（默认为 + 和 /）。[:graph:]将匹配任何可打印的非空白 ascii，包括 base64 缺少的许多符号/标点符号。因此使用tr -dC '[:graph:]'将导致更随机的输出，并具有更好的输入/输出效率。
I often use < /dev/random stdbuf -o0 tr -Cd '[:graph:]' | stdbuf -o0 head --bytes 32for generating strong passwords.
我经常< /dev/random stdbuf -o0 tr -Cd '[:graph:]' | stdbuf -o0 head --bytes 32用于生成强密码。
回答by Serg
cat /dev/urandom | tr -dc 'a-zA-Z0-9'
回答by greyfade
You can do more interesting stuff with BASH's FIFO pipes:
你可以用 BASH 的 FIFO 管道做更多有趣的事情：
uuencode <(head -c 200 /dev/urandom | base64 | gzip)
