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sdiff

text processingLinux/Unix

The sdiff command is one of the most frequently used commands in Linux/Unix-like operating systems. sdiff Side-by-side merge of file differences

See Examples View Syntax

Quick Reference

Command Name:

sdiff

Category:

text processing

Platform:

Linux/Unix

Basic Usage:

sdiff [options] [arguments]

Common Use Cases

Syntax

sdiff [options] file1 file2

Options

Option	Description
`-a, --text`	Treat all files as text
`-b, --ignore-space-change`	Ignore changes in the amount of white space
`-B, --ignore-blank-lines`	Ignore changes where lines are all blank
`-d, --minimal`	Try hard to find a smaller set of changes
`-E, --ignore-tab-expansion`	Ignore changes due to tab expansion
`-i, --ignore-case`	Ignore case differences in file contents
`-I RE, --ignore-matching-lines=RE`	Ignore changes whose lines all match regular expression RE
`-l, --left-column`	Output only the left column of common lines
`-o FILE, --output=FILE`	Operate interactively, sending output to FILE
`-s, --suppress-common-lines`	Do not output common lines
`-t, --expand-tabs`	Expand tabs to spaces in output
`-v, --version`	Output version information and exit
`-w NUM, --width=NUM`	Output at most NUM (default 130) print columns
`-W, --ignore-all-space`	Ignore all white space
`-Z, --ignore-trailing-space`	Ignore white space at line end
`--help`	Display this help and exit

Examples

How to Use These Examples

The examples below show common ways to use the sdiff command. Try them in your terminal to see the results. You can copy any example by clicking on the code block.

# Basic Examples Basic

sdiff file1.txt file2.txt

Display the differences between file1.txt and file2.txt side by side.

sdiff -s file1.txt file2.txt

Show only the differences between the files (suppress common lines).

# Advanced Examples Advanced

sdiff -w 100 file1.txt file2.txt Set the output width to 100 columns for better formatting. sdiff -l file1.txt file2.txt Use a simpler output format with line numbers. sdiff -o merged.txt file1.txt file2.txt Interactively merge file1.txt and file2.txt into merged.txt. sdiff -i file1.txt file2.txt Ignore case differences when comparing the files. sdiff -a file1.txt file2.txt Treat all files as text files, even if they contain binary data. sdiff -b file1.txt file2.txt Ignore changes in the amount of white space. sdiff -B file1.txt file2.txt Ignore changes where lines are all blank. sdiff -Z file1.txt file2.txt Ignore trailing white space at the end of lines.

Try It Yourself

Practice makes perfect! The best way to learn is by trying these examples on your own system with real files.

Understanding Syntax

Pay attention to the syntax coloring: commands, options, and file paths are highlighted differently.

Notes

The `sdiff` command is a powerful utility for comparing two files side by side and highlighting their differences. It's part of the GNU diffutils package and provides a visual alternative to the standard `diff` command, making it easier to see exactly how files differ from each other. The side-by-side format displays content from the first file in the left column and content from the second file in the right column, with a center column containing symbols that indicate how the lines relate to each other: - `|` (vertical bar): Indicates lines that are the same in both files - `<` (less than): Indicates a line that appears only in the left file - `>` (greater than): Indicates a line that appears only in the right file - `(` and `)`: Indicate that the lines between them need to be changed to convert the left file to the right file One of the most valuable features of `sdiff` is its interactive merge mode, activated with the `-o` option. In this mode, `sdiff` presents each difference and prompts for an action, allowing you to create a merged file that combines changes from both input files. This makes it an excellent tool for resolving conflicts in text files or combining changes from different versions. Key use cases for `sdiff` include: 1. Code Review: Examining changes between different versions of source code files. 2. Configuration Management: Comparing configuration files across systems or environments. 3. Document Editing: Reviewing changes to text documents, scripts, or other text-based files. 4. Conflict Resolution: Interactively merging changes from different versions of files. 5. Log Analysis: Comparing log files to identify differences in system behavior. The command provides numerous options for controlling how differences are detected and displayed. You can ignore case differences, whitespace variations, blank lines, and even lines matching specific patterns. These options help focus on meaningful differences while ignoring formatting or stylistic variations. While `sdiff` is extremely useful for text files, it may not produce meaningful results for binary files or files with very long lines. For binary files, other specialized comparison tools may be more appropriate. For files with long lines, the `-w` option allows you to increase the display width, though terminal limitations may still apply. For users who prefer graphical interfaces, tools like `meld`, `kdiff3`, or `vimdiff` provide similar functionality with more visual features, but `sdiff` remains valuable for its simplicity, availability on most Unix-like systems, and ease of use in scripts and terminal environments.

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Use Cases

Learn By Doing

The best way to learn Linux commands is by practicing. Try out these examples in your terminal to build muscle memory and understand how the sdiff command works in different scenarios.

See Examples Try Lab Exercises

$ sdiff

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