Randomly shuffling lines in Linux / Bash

Question

I have some files in linux. For example 2 and i need shuffling the files in one file.

For example

$cat file1
line 1
line 2
line 3
line 4
line 5
line 6
line 7
line 8

and

$cat file2
linea one
linea two
linea three
linea four
linea five
linea six
linea seven
linea eight

And later that i shuffling the two files i can obtain something like:

linea eight
line 4
linea five
line 1
linea three
line 8
linea seven
line 5
linea two
linea one
line 2
linea four
line 7
linea six
line 1
line 6

Answer 1

You should use shuf command =)

cat file1 file2 | shuf

Or with Perl :

cat file1 file2 | perl -MList::Util=shuffle -wne 'print shuffle <>;'