1 Introduction

seq(1) is a Unix command line tool that produces numbers 1, 2, etc, up until a count given by the user. For example, if the user runs seq 3, the output has the numbers 1, 2, and 3, one per line.

2 No arguments

Requirement: If seq is run without arguments, it reports an error.

3 No numbers

Requirement: If seq is run with the argument 0, it writes nothing.

4 One number

Requirement: If seq is run with the argument 1, it writes one line, with the number 1.

5 More than one number

Requirement: If seq is run with the argument 3, it writes three lines, one with the number 1, one with 2, and one with 3.

6 Not a number

Requirement: If seq is run with a non-numerical argument, it writes nothing to stdout, and an error message to stderr.