Table of Contents

1. Introduction
2. Common options
3. Output of entire files

3.1 cat: Concatenate and write files
3.2 tac: Concatenate and write files in reverse
3.3 nl: Number lines and write files
3.4 od: Write files in octal or other formats

4. Formatting file contents

4.1 fmt: Reformat paragraph text
4.2 pr: Paginate or columnate files for printing
4.3 fold: Wrap input lines to fit in specified width

5. Output of parts of files

5.1 head: Output the first part of files
5.2 tail: Output the last part of files
5.3 split: Split a file into fixed-size pieces
5.4 csplit: Split a file into context-determined pieces

6. Summarizing files

6.1 wc: Print byte, word, and line counts
6.2 sum: Print checksum and block counts
6.3 cksum: Print CRC checksum and byte counts
6.4 md5sum: Print or check message-digests

7. Operating on sorted files

7.1 sort: Sort text files
7.2 uniq: Uniquify files
7.3 comm: Compare two sorted files line by line
7.4 tsort: Topological sort
7.5 ptx: Produce permuted indexes

7.5.1 General options
7.5.2 Charset selection
7.5.3 Word selection and input processing
7.5.4 Output formatting
7.5.5 The GNU extensions to ptx

8. Operating on fields within a line

8.1 cut: Print selected parts of lines
8.2 paste: Merge lines of files
8.3 join: Join lines on a common field

9. Operating on characters

9.1 tr: Translate, squeeze, and/or delete characters

9.1.1 Specifying sets of characters
9.1.2 Translating
9.1.3 Squeezing repeats and deleting
9.1.4 Warning messages

9.2 expand: Convert tabs to spaces
9.3 unexpand: Convert spaces to tabs

10. Opening the software toolbox

Toolbox introduction
I/O redirection
The who command
The cut command
The sort command
The uniq command
Putting the tools together

Index