uncompress – Used to Decompress .Z Files

The uncompress command is used to decompress files that have been compressed using the .Z compression format. This command is a part of the compress package, which is used for compressing and decompressing files in Unix-based systems.


The basic syntax for using the uncompress command is as follows:

uncompress [options] file.Z

Here, file.Z is the name of the compressed file that you want to decompress. The uncompress command will replace the compressed file with the decompressed version of the file.


To decompress a file named example.txt.Z, you can use the following command:

uncompress example.txt.Z

This will create a new file named example.txt in the same directory as the compressed file.

Specific Use Cases

The uncompress command is useful in situations where you have a large number of files that have been compressed using the .Z format. You can use a shell script to automate the decompression process for all the files in a directory.


The following table lists all the available options for the uncompress command:

Option Description
-c Write output to standard output instead of overwriting the input file
-f Force decompression of the file, even if the output file already exists
-v Verbose mode – display the name of the file being decompressed

Troubleshooting Tips

  • If you get an error message that says “uncompress: corrupt input”, it means that the compressed file is damaged and cannot be decompressed.
  • If the output file already exists and you do not use the -f option, the uncompress command will not decompress the file and will display an error message.


  • The .Z compression format is an older compression format that is not used very often in modern systems. Other compression formats like .gzip and .zip are more commonly used.
  • The compress package that contains the uncompress command may not be installed on all Unix-based systems. You may need to install the package manually before you can use the command.