xdeview - a powerful decoder for binary files

Description

XDeview  is a smart decoder for attachments that you have received in encoded form via electronic mail or
       from the usenet. It  is  similar  to  the  standard  uudecode(1)  command,  yet  with  more  comfort  and
       flexibility.   XDeview  supports  the  uuencoding,xxencoding,Base64 and BinHex encoding methods, and is
       able to handle split-files (which have been sent in multiple parts) as well as multiple  files  at  once,
       thus  greatly  simplifying  the  decoding  process.  Usually, you will not have to manually edit files to
       prepare them for decoding.

       If you don't really need a graphical frontend for these kinds of jobs, have a  look  at  uudeview(1)  and
       uuenview(1).

       After  invoking  the  program,  it  will  scan  all the given files for encoded data. If any of them were
       directories, they will be recursively dived into.  You don't need to give files on the command line;  you
       can  also  select  files  later  from  within the program. After completing the initial scan, you will be
       presented with a list of files that seem like they can be decoded  properly.  You  can  then  pick  files
       individually for decoding.

Encoding Menu

When encoding files ("Encode" from the "File" menu), a large dialog box opens where you can set various
options for the file. If you selected multiple files for encoding, a status line at the top displays the
number of files left. The dialog itself stays open until all files have been handled.

Filename
The current file to encode. You cannot edit this field.

SendAs
The file name by which the file will be sent. Defaults to the filename stripped of all directory
information.

UseSubject
When mailing or posting, this text will be used as subject. The filename and part numbers are
added automatically, so you can choose to leave this line empty.

LinesperFile
Sets the number of encoded lines per part. Bigger files will be automatically split into multiple
parts. Use if you are posting files to a newsgroup, or if the recipient's system cannot handle
large files. A good splitting size is 1000 lines. "0" lines means not to split.

...Encoding
Selects the encoding method to use. If you wonder which one's the best, you might find a clue in
my article "Introduction to Decoding".

FileIn(Path)
Sets a directory where to encode the file to. The encoding will go to files with the same base
name as the original file, but with extensions of .001, .002 (depending on the number of necessary
parts as enforced by the "Lines per File" setting).

EmailTo
Give a comma-separated list of email addresses. This option might be disabled if your system does
not allow sending of emails.

PostTo
Here you can enter a comma-separated list of newsgroups to which the file should be posted. This
option might be disabled if your system does not support posting news.

NNTPServer
This field only appears on some systems, in the case that a news host is needed, but none was
configured at compile-time. If this field does appear, you must enter a valid host name here in
order for posting to work. If you don't want to post the file anyway, don't worry about it.

OK Performs the selected action(s) on this file and skips to the next one.

OKtoAll
Uses these settings for each file in question (does not prompt you for the other files), thus
sending all files at once.

Next Does not encode the file and skips to the next one (sorry, there's no button to skip backwards).

Cancel Cancels encoding and returns to the main menu.

File List

       The  File List is a list box displaying all the files that have been picked up while scanning the encoded
       data. These files are ready for decoding, previewing or anything. The list  can  be  scrolled  using  the
       scrollbar on the right of the list.

       Individual  files  can  be selected simply by clicking on them. Multiple files can be selected by holding
       down the CTRL key and clicking on the individual files.

Main Menu

       The main window of xdeview is composed of six main elements. At the top is the MenuBar.  Centered is the
       FileList, which lists all the files that have been detected in  the  encoded  data  and  are  ready  for
       decoding.  Left  of  the  File List is the StatusList, which describes the status of each file. Usually,
       this list will show "OK" for all files, as display of erroneous files is  normally  suppressed.   On  the
       right  is  a bunch of short-cut buttons with the most heavily-used functions. At the bottom of the window
       is the SavePath entry field, and the status bar. Each of these items will be described  individually  in
       the following text.

Menu Bar

FileMenuLoad...
Loads encoded files. These files are then scanned for encoded data and files; these files
are added to the File List. You can also select directories, which are then recursively
descended into

Encode Encode file(s), storing the encoded data on disk, sending them via email, or posting them
to newsgroups. See below.

Helpers
Xdeview reads information from your .mailcap and .mime.types to perform the appropriate
default action when you hit the "Execute" button. In this dialogue, you can configure the
locations of these files.

SaveSetup
Saves all current options, the input and output file paths etc. into the .xdeviewrc file in
your home directory. This file is automatically read upon startup, so the saved settings
will be set by default in future sessions. The resource file is actually a Tcl script which
you can edit with any editor.

Quit Exits the program.

Options
Set various options that modify the behaviour of the program. Note that most options only catch
for files read afterwards.

FastScanning
Sets fast scanning mode. The program will then assume that all input files contain at most
one encoded part (as it is true with files from a news spool). The scanning engine will be
sped up because it does not have to read each input file completely but stops scanning
after encoded data has been found.

The decoder has to disable some safety options in fast mode, so certain problems with the file
will only be detected when finally decoding the file.

AutomaticOverwrite
When decoding a file which is already present in the target directory, the user will be
asked whether the file shall be overwritten. By enabling this option, target files will be
overwritten without asking.

DesperateMode
Usually, you will only be presented files to which all parts have been found. Enabling
Desperate Mode, you'll also get to see the other files as well, with an appropriate
description of the problem in the Status List. In desperate mode, the decoder will also
try to detect short Base64 files outside of MIME messages. This is normally disabled,
because these desperate tries to find Base64 encoding may cause misdetection of encoded
data, again resulting in invalid files.

VerboseMode
Opens a separate text box to which additional messages will be written while scanning the
input files. These messages are extremely helpful for finding out what went wrong if files
cannot be decoded properly.

AlternateBracketPolicy
Changes the heuristics by which the decoder tries to extract a part number from the subject
line. The algorithm usually gives numbers in braces () higher priority than numbers in
brackets []. If both kinds of brackets are present, and their use is conflicting (for
example if both the part number and a series number are given), then you may have to
explicitly select the bracket policy. If this option is false (default), then the "part
number" is taken from the braces (), otherwise from the brackets [].

DumbMode
Disables automatic part number detection by parsing the subject line. Use if xdeview fails
to pick up the correct part numbers. Note that with the option set, the parts must be
correctly ordered in the input files. Also, missing parts will not be detected this way.

HandleTextFiles
Usually, XDeview only presents encoded data for decoding. With this option set, text parts
from MIME messages and non-encoded messages are also offered. Plaintext messages frequently
don't have an associated filename, so they're assigned a unique name from a sequential
four-digit number.

AutoInfo
Opens up the information window whenever you click on a file in the File List.

RemoveInputFiles
With this option set, input files are removed if any file was successfully decoded from
them. Use with care! UUDeview only checks if any data was decoded from an input file, but
does not care about any other contents of that input file, or whether a file also held an
incomplete attachment.

MIMECompliance
Be more strict when reading MIME input files.

ActionsDecode Decode the selected file(s).

Rename Rename the selected file(s), for example if the filename conflicts with existing files, or
if the name doesn't meet system limitations.

DecodeAll
Decode all files currently visible in the File List.

Info Displays available info on the currently selected file (if more than one file is selected,
only info for the first will be displayed). This is the zeroeth part of a file, if
available, or the header of the first part up to the beginning of encoded data.

Execute
Runs an external program with the currently selected file. A program is selected by first
looking at the Content-Type of the message, if available, then by checking the file's
extension. The appropriate information is read from your .mailcap and .mime.types files
(although the handling of information in .mailcap files is currently incomplete). If no
matching type is found, a dialog box pops up where you can enter any command.

ListTextFile
This is for the rare cases when a text file has been sent through the net in encoded form.
Use this action only when you know the file in question is in fact a text file, otherwise
you'll get a load of trash on the screen.

HelpAbout A short message from the Author.

License
Displays the license under which xdeview is distributed, the GPL. Read it, or you'll hear
from my lawyers.

Name

       xdeview - a powerful decoder for binary files

Notes

       If  you  cannot execute xdeview, and it reports something like "command not found", but are sure that the
       file itself can be found, check the reference to the main file uuwish at the top of the file.

Options

There's no real need to set options on the command line; they can also be set from within the program.
Note that options must be preceded by a double-hyphen '--', otherwise they might be mistaken for display
options.

-d Sets the program into desperate mode. It will then offer you to decode incomplete files. This is
useful if you are missing the last part of a 50-parts posting, but in most cases the desperately-
decoded files will simply be corrupt and unusable. The degree of usefulness of an incomplete file
depends on the file type.

-f Uses fast mode for file scanning. The program assumes that each input file holds at most one part,
which is usually true for files in a news spool directory. This option breaksdecoding of input
files with multiple articles. Also, certain sanity checks are disabled, probably causing erroneous
files to be presented for decoding. Sometimes you'll get error messages when decoding, sometimes
you'll just receive invalid files. Don't use -f if you can't live with these problems.

-o Gives the OK to overwrite files already there on decoding. The default is to prompt the user
whether to overwrite, rename or skip the file.

-v Disables verbosity. Normally, the program prints some status messages while reading the input
files, which can be very helpful if something should go wrong. Use if these messages disturb you.

-ppath
Sets the path where decoded files shall be written to. This must be a valid pathname, or you'll
get errors when trying to decode anything. Defaults to the current working directory.

-b This changes xdeview's policy of finding a part number on a subject line and may only be needed in
some rare cases when part numbers are found in () parentheses as well as in [] brackets, for
example in a series of multi-part postings. By default, xdeview uses the numbers found in ()
parentheses first. But if this number indicates the file's number in the series and the part
number is given in [] brackets, use this parameters to make the program read the other number
first. This does not affect decoding of files with only one or neither type of brackets. If you
prefer, you can also use the option as -b[]-s Read "minus smartness". This option turns off automatic part number detection from the subject
line. Try this option if xdeview fails to parse the subject line correctly and makes errors at
guessing part numbers, resulting in incorrect ordering of the parts. With this option, parts are
always put together sequentially (so the parts must be correctly ordered in the input file).
Note: The correct part number found in proper MIME files is still evaluated.

-t Use plaintext messages. Usually, XDeview only presents encoded data for decoding. With this option
set, text parts from MIME messages and non-encoded messages are also offered. Plaintext messages
frequently don't have an associated filename, so they're assigned a unique name from a sequential
four-digit number.

Runtime Messgages

If you have enabled verbose mode, progress messages will appear in an own text window titled RuntimeMessages. The messages generated during the scanning phase are extremely helpful in tracing what the
program does, and can be used to figure out the reason why files cannot be decoded, if you understand
them. This section explains how to interpret them. Understanding this section is not necessary to operate
the program.

First, there are "Loading" messages, which begin with the string "Loaded". Each line should feature the
following items:

SourceFile
The first item is the source file from which a part was loaded. Many parts can be detected within
a single file.

SubjectLine
The complete subject is reproduced in single quotes.

Identifier
The program derives a unique identification for this thread from the subject line, for grouping
articles that look like they belong to the same file. The result of this algorithm is presented in
braces.

Filename
If a filename was detected on the subject line or within the data (for example, on a begin line,
or as part of the Content-Type information).

PartNumber
The part number derived from the subject line, or, in the case of properly MIME-formatted
messages, from the "part" information.

Begin/End
If a "begin" or "end" token was detected, it is printed here.

EncodingType
If encoded data was detected within this part, either "UUdata", "Base64", "XXdata" or "Binhex" is
printed here.

More messages are printed after scanning has completed. A single line will be printed for each group of
articles. The contents of this line are best understood by looking at an example. Here is one:

Found'mailfile.gz'State16UUDataPartsbegin12345end6OK

This indicates that the file mailfile.gz has been found. The file was uuencoded ("UUData") and consists
of 6 parts. The "begin" token was found in the first part, and the "end" token was found in the sixth
part. Because it looks like everything's there, this file is tagged as being "OK". The State is a set of
bits, where the following values may be or'ed:

1 Missing Part

2 No Begin

4 No End

8 No encoded data found.

16 File looks Ok

32 An error occurred during decoding of the file.

64 File was successfully decoded.

Save Path

       This is the path where decoded files will be written to.

Setup File

       If it exists, the file .xdeviewrc in your home directory will be executed in the Tcl  interpreter  during
       program  initialization.  It  must  be  a  valid Tcl program, which you can use to set certain options by
       default. For the Tcl-illaterate: variables can be set using the following syntax:
       setvar_namevalue
       The following variables (options) can be set (look at the text above for an explanation of  what  they're
       doing)

       OptionFast
              If set to 1, use fast scanning mode.

       OptionBracket
              If set to 1, use the alternate bracket policy.

       OptionOverwrite
              If set to 1, assume it's Ok to overwrite files without asking.

       OptionDesperate
              If set to 1, switch into desperate mode.

       OptionVerbose
              If set to 1, print progress messages.

       SaveFilePath
              This is a string variable with the default Save Path, where you want decoded files to go.

       EncodeMaxLines
              Maximum number of lines per file for encoding. "0" for unlimited.

       EncodeEncoding
              Default encoding to use. "0" for UUencoding, "1" for XXencoding and "2" for Base64 encoding.

       NNTPServer
              The  address  of  your NNTP server (only needed on some systems). Can also be set (preferredly) in
              your environment variable NNTPSERVER.

Short-Cut Buttons

       The buttons on the right side of the window are short-cuts for the menu items. Read the discussion of the
       Main Menu items above for an explanation.

Status

       A short message what the program is currently doing or what it expects you to do.

Status List

       The Status Lists notes the corresponding status for each file in the FileList, Usually, you'll just  see
       "OK" here; otherwise, an error message is shown describing why the file cannot be decoded properly. There
       are the following states:

       OK     All  parts  of  the file have been found, and the encoded data looks correct on first sight. There
              are certain problems that might only appear when decoding the  file,  but  usually  everything  is
              fine.

       Incomplete
              This  file  is missing one or more parts. If you decode this file, the output data will be corrupt
              and usually unusable.

       NoBegin
              The file doesn't have a beginning. The decoded file will be most certainly corrupt and unusable.

       NoEnd No end was found on the file. This usually means that one or more parts at the  end  are  missing.
              The degree of usefulness of a decoded file depends on the file type.

       Error  A previous attempt to decode the file has failed.