37

I need to create a text file which should contain random text data that can be read by human. I know that we can use /dev/urandom and /dev/random for getting random data. But it is not readable by humans. I need to create a file which contains random text format. Is there any way to do that?

  • 1
    "Readable by humans" as in making actual sense? Full sentences? Or just some dictionary words? – slhck Dec 23 '13 at 12:13
81

We can do it by following command

base64 /dev/urandom | head -c 10000000 > file.txt

It creates a file with name file.txt size of 10 MB.

11

get the output of:

tr -dc A-Za-z0-9 </dev/urandom 

and pipe it to a file.

You can use head command with -c or -n to limit the file size

example to generate a 1kB file a.txt:

tr -dc A-Za-z0-9 </dev/urandom | head -c 1024 > a.txt
4

base64 seems to only output alphanumeric characters plus / and +.

I like this to get more "punctuation" characters, like

'[:punct:]'
  Punctuation characters; in the 'C' locale and ASCII character
  encoding, this is ! " # $ % & ' ( ) * + , - . / : ; < = > ? @ [ \
  ] ^ _ ` { | } ~

So use this:

'[:graph:]'
     Graphical characters: '[:alnum:]' and '[:punct:]'

and use tr to remove single quotes ' backticks ` and backslashes \

tr -dc '[:graph:]' < /dev/urandom | tr -d \''\\'\` | head -c [size]

the -c size option to head can have a multiplier suffix: b 512, kB 1000, K 1024, MB 1000*1000, M 1024*1024, GB 1000*1000*1000, G 1024*1024*1024, and so on for T, P, E, Z, Y.

2

If you don't have /dev/urandom (because maybe you're using a GitBash console), you can use:

openssl rand 33000 -base64 -out dump.txt

Your Answer

By clicking "Post Your Answer", you acknowledge that you have read our updated terms of service, privacy policy and cookie policy, and that your continued use of the website is subject to these policies.

Not the answer you're looking for? Browse other questions tagged or ask your own question.