splitdiff Command in Linux
The splitdiff command is a useful tool designed to split unified diffs into individual files. Unified diffs are widely used in version control systems like Git, and they often contain changes made to multiple files. By using splitdiff, you can break these combined diffs into smaller, file-specific diffs, enabling more targeted debugging, patch management, or analysis.
Table of Contents
Here is a comprehensive guide to the options available with the splitdiff command −
- Overview of splitdiff Command
- Installing splitdiff Command
- Syntax of splitdiff Command
- splitdiff Command Options
- Examples of splitdiff Command in Linux
Overview of splitdiff Command
Unified diffs usually combine changes in multiple files into one output, which is hard to manage. The splitdiff command solves this by splitting the merged diff into separate files. Each output file contains changes for a single file, which is simpler to apply patches or review changes.
Installing splitdiff Command
The splitdiff command is part of the patchutils package and has several utilities for patch file manipulation. In order to install splitdiff, you must have the patchutils package installed in your Linux system. Below are steps to install splitdiff on certain widely used Linux distributions −
On Debian / Ubuntu-Based Systems
sudo apt install patchutils
On Red Hat / CentOS-Based Systems
sudo yum install patchutils
On Fedora
sudo dnf install patchutils
Syntax of splitdiff Command
The basic syntax for the splitdiff command is as follows −
splitdiff [options] [input_diff]
Where,
- input_diff − The unified diff file that you want to split into individual diffs. If omitted, splitdiff reads from standard input.
- options − Flags to customize the output, such as modifying file names or adjusting verbosity.
splitdiff Command Options
The splitdiff command provides multiple customizable options to meet diverse needs.
| Option | Description |
|---|---|
| -a | Split each individual file-level patch out of the unified diff. |
| -p N | Ignore the first N pathname components when generating output filenames. |
| -d | Use output file names like a_b.c.patch for a/b.c to replace slashes (/) in file names with underscores (_). |
| -D dir | Create output files in the specified subdirectory (dir). |
| -E | Remove empty diff files. If there are no useful changes in a diff, this option does not delete any empty files from the output. |
Examples of splitdiff Command in Linux
Here are a few practical examples of splitdiff command on Linux environment −
- Breaking Unified Diff into Individual Patches
- Ignoring Directory Components in Pathnames
- Flattening Output Filenames with Underscores
- Saving Output in a Specific Directory
- Removing Empty Patch Files
Breaking Unified Diff into Individual Patches
A unified diff file typically contains changes for more than one file. You may split these changes into single file-specific patches to handle them more conveniently.
splitdiff -a combined.patch
This command shatters combined.patch, identifies the changes made to each file, and generates an independent patch file for each of them.
Ignoring Directory Components in Pathnames
Sometimes unified diffs have deeply nested file paths that are not required in the output filenames. You can omit specific pathname components to get cleaner and less verbose file names.
splitdiff -p 1 combined.patch
With this command, splitdiff removes the first directory from each file path.
Flattening Output Filenames with Underscores
Creating patches for files without nested directory structures can simplify file organization. This is particularly useful when working in environments that donât support hierarchical directories.
splitdiff -d combined.patch
This command replaces directory separators (/) with underscores (_) in the output file names.
Saving Output in a Specific Directory
Organizing split patches in a designated directory can help keep your workspace neat and improve collaboration with teammates.
splitdiff -D patches combined.patch
The splitdiff command creates a directory named patches (if it doesnât exist already) and saves all split patch files there.
Removing Empty Patch Files
Unified diffs often include empty changes for placeholder files or entries without modifications. You can exclude these irrelevant patches from the output to keep the results clean and focused.
splitdiff -E combined.patch
If any file-level diffs within combined.patch donât contain actual changes, splitdiff automatically skips creating output files for them.
Conclusion
The splitdiff command is a very handy tool to make unified diff management more efficient in version control systems like Git. Breaking merged diffs into file-specific patches, splitdiff enables more focused debugging, patch application, and review work. Its built-in functionalities like directory setup and pathname adjustments allow it to accommodate various types of workflows.
Regardless of whether you are working on collaborative projects or changesets, splitdiff is a necessity to improve patch management and improve productivity.