Take a Backup before Applying the Patch using -b
You can make a backup copy of the original file before applying a patch. This is done using the -b option with the following patch command.
Command :
patch -b < patch_file
After running this, you’ll have a new file with the “.orig” extension, which is a backup of the original file before the patch was applied. For example, if patching hello.c use the below command.
Command :
patch -b < hello.patch
Output :
This will create a backup file called “hello.c.orig”.
You can also customize the backup file name format using the -V option along with -b:
patch -b -V numbered < patch_file
This will create a backup file with a numbered extension, like “hello.c.1”.
So in summary, -b creates a backup, and -V numbered lets you choose a numbered backup file name format instead of the default “.orig” extension.
How to Run Patch Command in Linux?
Sometimes, you install software by compiling it from source code instead of using package managers like yum or apt-get. When a security fix is available for such software, you can’t just upgrade it like you normally would. Instead, you must download the security patch, apply it to the source code, and then recompile the software.
This article explains how to create and apply the diff and patch commands. A patch file contains the differences between two versions of the same file or source code. It is made using the diff command and applied using the patch command.
Run Patch Command in Linux
- Syntax of running patch command in Linux
- Application of the Patch File
- Options and descriptions for patch command
- Create a Patch File using diff
- Apply Patch File using Patch Command
- Create a Patch From a Source Tree
- Apply Patch File to a Source Code Tree
- Take a Backup before Applying the Patch using -b
- Validate the Patch without Applying (Dry-run Patch File)
- How to Undo/Reverse a Patch