uuencode - macOS


uuencode converts binary files into a text representation using the uuencoding scheme, allowing them to be transmitted through channels that only support text. It is primarily used for encoding binary data for transmission via email, web forms, or other text-based communication methods.


uuencode [options] [-t file] [name]

Required Arguments

| Argument | Description |
| name | Name of the file to encode. |

Optional Arguments

| Option | Description |
| -t file | Specify an auxiliary file containing translation rules for the encoding. |
| -m | Encode multiple files. |
| -d | Decode a uuencoded file. |
| -c | Check the integrity of a uuencoded file. |
| -r | Restore the original file hierarchy when decoding. |
| -i | Convert the encoded file into a specified format. |
| -x | Display a list of supported formats. |
| -h | Display help information. |
| -v | Display version information. |


  • -t file

    Allows for customization of the encoding process using a translation rules file.

  • -m

    Encodes multiple files into a single uuencoded file.

  • -d

    Decodes a uuencoded file into its original binary format.

  • -c

    Performs a checksum check to verify the integrity of a uuencoded file.

  • -r

    When decoding, recreates the original file hierarchy, including directory structure.

  • -i

    Converts the decoded file into a specified format, such as Base64 or uuencode.

  • -x

    Lists the supported formats for the -i option.


Encode a file:

uuencode file.txt file.txt.uu

Decode a uuencoded file:

uuencode -d file.txt.uu file.txt

Encode and decode a file using a translation rules file:

uuencode -t rules.txt file.txt file.txt.uu
uuencode -t rules.txt -d file.txt.uu file.txt

Encode multiple files into a single uuencoded file:

uuencode -m file1.txt file2.txt ... file.uu

Common Issues

  • Filename too long: Ensure that the filename of the encoded file is within the allowable length for the target system.
  • Invalid translation rules file: Verify that the translation rules file specified with the -t option is formatted correctly.
  • File not encoded properly: Check for any special characters or binary data in the file that may interfere with the encoding process.


Combine with email: Send uuencoded files as attachments in email messages to ensure they are transmitted correctly.

Use in scripts: Automate the encoding and decoding of files within shell scripts or command pipelines.

  • uudecode: Decodes uuencoded files.
  • base64: Converts binary data into a base64 encoded string.