Top (Comparing and Merging Files)

Overview
1 What Comparison Means
- 1.1 Hunks
- 1.2 Suppressing Differences in Blank and Tab Spacing
- 1.3 Suppressing Differences Whose Lines Are All Blank
- 1.4 Suppressing Differences Whose Lines All Match a Regular Expression
- 1.5 Suppressing Case Differences
- 1.6 Summarizing Which Files Differ
- 1.7 Binary Files and Forcing Text Comparisons
2 diff Output Formats
- 2.1 Two Sample Input Files
- 2.2 Showing Differences in Their Context
- 2.3 Showing Differences Side by Side
  - 2.3.1 Controlling Side by Side Format
  - 2.3.2 An Example of Side by Side Format
- 2.4 Showing Differences Without Context
  - 2.4.1 An Example of Normal Format
  - 2.4.2 Detailed Description of Normal Format
- 2.5 Making Edit Scripts
- 2.6 Merging Files with If-then-else
3 Incomplete Lines
4 Comparing Directories
5 Making diff Output Prettier
- 5.1 Preserving Tab Stop Alignment
- 5.2 Omitting trailing blanks
- 5.3 Paginating diff Output
6 diff Performance Tradeoffs
7 Comparing Three Files
- 7.1 A Third Sample Input File
- 7.2 An Example of diff3 Normal Format
- 7.3 Detailed Description of diff3 Normal Format
- 7.4 diff3 Hunks
8 Merging From a Common Ancestor
- 8.1 Selecting Which Changes to Incorporate
- 8.2 Marking Conflicts
- 8.3 Generating the Merged Output Directly
- 8.4 How diff3 Merges Incomplete Lines
- 8.5 Saving the Changed File
9 Interactive Merging with sdiff
- 9.1 Specifying diff Options to sdiff
- 9.2 Merge Commands
10 Merging with patch
- 10.1 Selecting the patch Input Format
- 10.2 Revision Control
- 10.3 Applying Imperfect Patches
- 10.4 Creating and Removing Files
- 10.5 Updating Timestamps on Patched Files
- 10.6 Multiple Patches in a File
- 10.7 Applying Patches in Other Directories
- 10.8 Backup Files
- 10.9 Backup File Names
- 10.10 Reject File Names
- 10.11 Messages and Questions from patch
- 10.12 patch and the POSIX Standard
- 10.13 GNU patch and Traditional patch
11 Tips for Making and Using Patches
- 11.1 Tips for Patch Producers
- 11.2 Tips for Patch Consumers
- 11.3 Avoiding Common Mistakes
- 11.4 Generating Smaller Patches
12 Invoking cmp
- 12.1 Options to cmp
13 Invoking diff
- 13.1 Options to diff
14 Invoking diff3
- 14.1 Options to diff3
15 Invoking patch
- 15.1 Options to patch
16 Invoking sdiff
- 16.1 Options to sdiff
17 Standards conformance
18 Future Projects
- 18.1 Suggested Projects for Improving GNU diff and patch
- 18.2 Reporting Bugs
Appendix A Copying This Manual
Appendix B Translations of This Manual
Appendix C Index

Comparing and Merging Files

This manual is for GNU Diffutils (version 3.7, 7 January 2018), and documents the GNU diff, diff3, sdiff, and cmp commands for showing the differences between files and the GNU patch command for using their output to update files.


• Overview		Preliminary information.
• Comparison		What file comparison means.
• Output Formats		Formats for two-way difference reports.
• Incomplete Lines		Lines that lack trailing newlines.
• Comparing Directories		Comparing files and directories.
• Adjusting Output		Making `diff` output prettier.
• diff Performance		Making `diff` smarter or faster.

• Comparing Three Files		Formats for three-way difference reports.
• diff3 Merging		Merging from a common ancestor.

• Interactive Merging		Interactive merging with `sdiff`.

• Merging with patch		Using `patch` to change old files into new ones.
• Making Patches		Tips for making and using patch distributions.

• Invoking cmp		Compare two files byte by byte.
• Invoking diff		Compare two files line by line.
• Invoking diff3		Compare three files line by line.
• Invoking patch		Apply a diff file to an original.
• Invoking sdiff		Side-by-side merge of file differences.

• Standards conformance		Conformance to the POSIX standard.
• Projects		If you’ve found a bug or other shortcoming.

• Copying This Manual		How to make copies of this manual.
• Translations		Available translations of this manual.
• Index		Index.

Comparing and Merging Files

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Comparing and Merging Files