(PECL mailparse >= 0.9.0)
mailparse_msg_extract_part_file — Extracts/decodes a message section
$mimemail
   , mixed $filename
   [, callable $callbackfunc
  ] )Extracts/decodes a message section from the supplied filename.
The contents of the section will be decoded according to their transfer encoding - base64, quoted-printable and uuencoded text are supported.
mimemailA valid MIME resource, created with mailparse_msg_create().
filenameCan be a file name or a valid stream resource.
callbackfunc
       If set, this must be either a valid callback that will be passed the
       extracted section, or NULL to make this function return the
       extracted section.
      
If not specified, the contents will be sent to "stdout".
   If callbackfunc is not NULL returns TRUE on
   success.
  
   If callbackfunc is set to NULL, returns the
   extracted section as a string.
  
   Returns FALSE on error.