shuf

Shuf is a command-line utility in Unix-like operating systems, including Linux and macOS, used for generating random permutations of input lines. It is part of the GNU core utilities package and is often used for shuffling data, creating random samples, or generating random numbers. The name "shuf" is a contraction of "shuffle".

Shuf can read input from standard input, a file, or a range of numbers. When used with a file, it reads the file line by line and outputs the lines in a random order. When used with a range of numbers, it generates a sequence of numbers within the specified range and outputs them in random order.

The basic syntax for using shuf is:

shuf [OPTION]... [FILE]

Some common options include:

-e, --echo: Treat each argument as an input line.

-i, --input-range=LO-HI: Treat each number LO through HI as an input line.

-n, --head-count=COUNT: Output at most COUNT lines.

-o, --output=FILE: Write result to FILE instead of standard output.

Shuf is particularly useful for tasks such as creating randomized test data, shuffling a list of names, or generating random sequences for simulations. It is a simple yet powerful tool for anyone working with command-line interfaces and data manipulation.