{
    "mode": "man",
    "parameter": "uuencode",
    "section": "5",
    "url": "https://www.chedong.com/phpMan.php/man/uuencode/5/json",
    "generated": "2026-06-02T18:06:35Z",
    "sections": {
        "NAME": {
            "content": "uuencode - format of an encoded uuencode file\n",
            "subsections": []
        },
        "DESCRIPTION": {
            "content": "Files output by uuencode(1) consist of a header line, followed by a number of body lines, and\na trailer line.  The uudecode(1) command will ignore any lines preceding the header  or  fol‐\nlowing the trailer.  Lines preceding a header must not, of course, look like a header.\n\nThe  header  line  is  distinguished  by having the first 5 characters be begin followed by a\nspace, or else a hyphen and either base64 or encoded or both (also separated with a  hyphen).\nThe  base64  option says the file has been encoded using base64.  The encoded option says the\noutput file name has been base64 encoded.  It is never encoded with  traditional  uuencoding.\nThis  is  a GNU extension.  These are followed by a mode (in octal), and a string which names\nthe remote file.  The mode is separated from the begin clause and the file name by  a  single\nspace character.\n",
            "subsections": [
                {
                    "name": "Traditional uuencoding",
                    "content": "The traditional uuencoded file body consists of a number of lines, each at most 62 characters\nlong (including the trailing newline). These consist of a character count letter, followed by\nthe  encoded  characters,  followed  by  a newline.  The character count is a single printing\ncharacter, and represents an integer, the number of bytes the rest of  the  line  represents.\nSuch  integers  are always in the range from 0 to 63 and can be determined by subtracting the\ncharacter space (octal 40) from the character.\n\nGroups of 3 bytes are stored in 4 characters, 6 bits per character.   All  are  offset  by  a\nspace  to  make  the  characters  printing.   The last line may be shorter than the normal 45\nbytes.  If the size is not a multiple of 3, this fact can be determined by the value  of  the\ncount  on the last line.  Extra garbage will be included to make the character count a multi‐\nple of 4.  The body is terminated by a line with a count of zero.  This line consists of  one\nASCII space.\n\nThe trailer line consists of end on a line by itself.\n"
                },
                {
                    "name": "base64 encoding",
                    "content": "base64  encoded  files  follow  the  specified format for the body, but also include a begin-\nbase64 header and a trailer line of four = characters.\n"
                }
            ]
        },
        "EXAMPLES": {
            "content": "begin-base64-encoded 644 VE9ETw==\nThis introduces a base64 encoded file named, TODO with that name encoded using base64  encod‐\ning.\n\nbegin-encoded 644 5$]$3P``\nThis introduces an encoded file named, TODO with that name encoded using uuencoding.  The en‐\ncoding is a lot less friendly.  Please prefer base64 encoding.\n",
            "subsections": []
        },
        "CONFORMING TO": {
            "content": "IEEE Std 1003.1, plus extensions\n\nThe -encoded suffix to the begin header line is a GNU extension.  Recipients  must  have  the\nGNU uudecode program to decode them.\n",
            "subsections": []
        },
        "SEE ALSO": {
            "content": "uuencode(1), uudecode(1), base64(1GNU)\n",
            "subsections": []
        },
        "HISTORY": {
            "content": "The uuencode file format appeared in BSD 4.0 .\n\n\n\nUUENCODE(5)",
            "subsections": []
        }
    },
    "summary": "uuencode - format of an encoded uuencode file",
    "flags": [],
    "examples": [
        "begin-base64-encoded 644 VE9ETw==",
        "This introduces a base64 encoded file named, TODO with that name encoded using base64  encod‐",
        "ing.",
        "begin-encoded 644 5$]$3P``",
        "This introduces an encoded file named, TODO with that name encoded using uuencoding.  The en‐",
        "coding is a lot less friendly.  Please prefer base64 encoding."
    ],
    "see_also": [
        {
            "name": "uudecode",
            "section": "1",
            "url": "https://www.chedong.com/phpMan.php/man/uudecode/1/json"
        },
        {
            "name": "base64",
            "section": "1GNU",
            "url": "https://www.chedong.com/phpMan.php/man/base64/1GNU/json"
        }
    ],
    "tldr": {
        "source": "official",
        "description": "Encode binary files into ASCII for transport via mediums that only support simple ASCII encoding.",
        "examples": [
            {
                "description": "Encode a file and print the result to `stdout`",
                "command": "uuencode {{path/to/input_file}} {{output_file_name_after_decoding}}"
            },
            {
                "description": "Encode a file and write the result to a file",
                "command": "uuencode -o {{path/to/output_file}} {{path/to/input_file}} {{output_file_name_after_decoding}}"
            },
            {
                "description": "Encode a file using Base64 instead of the default uuencode encoding and write the result to a file",
                "command": "uuencode {{-m|--base64}} -o {{path/to/output_file}} {{path/to/input_file}} {{output_file_name_after_decoding}}"
            }
        ]
    }
}