Pocket UnZip


Table of Contents


Why use Pocket UnZip for Windows CE?


Key Features of Pocket UnZip


Installing Pocket UnZip

Place PUNZIP.EXE and PUNZIP.HTP (optional help file) into your \Windows directory on your H/PC.

From your H/PC's Start Menu, choose Run..., enter "punzip", and tap OK.

The first time you run Pocket UnZip, it will register itself as the application for handling Zip files. From then on, you can just double-tap on Zip files in Explorer or from your Desktop to open them in Pocket UnZip.


Opening a Zip File

There are several ways to open a Zip file.


Zip File Listing

Pocket UnZip's main view displays a list of files, directories, and volume labels that are stored within the currently loaded Zip file. This list can be displayed in two modes, normal and expanded. The normal mode is sufficient for most users. It contains the following information for every item in the Zip file:

Expanded mode contains all the above information, plus the following additional information:

You may toggle between the normal view and the expanded view by selecting the Extended View option from the View menu, or by tapping the associated toolbar button.


Properties Dialog

The properties dialog is useful for viewing detailed information for one or more files. It is invoked by selecting one or more files in the file list and then choosing Properties from the File menu. For convenience, you can also tap the toolbar button or press Alt+Enter.

If one file is selected, the properties dialog will show you detailed information about that one file and its comment.

If multiple files are selected, the dialog will show you combined results for all the files selected. Cumulative results will be given for the file count, byte counts, and compression ratio. Merged results will be given for the compression method, date, CRC, attributes, and comment. For the date, all values that are common between the selected files (such as year), will be shown with their common value. All values that differ between the selected files will be shown as question marks. For attributes, a black check means that all selected files have that particular attribute, a gray check mark means that some of the selected files have that attribute, and no check mark means that none of the selected files have that attribute.

By using the properties dialog with multiple files, you can determine things like... What is the total number of files or bytes in the Zip file? What is the total compression ratio for all selected files. Are all the selected files from the same year? Same month? How many files have comments?


File Comments

Zip files provide two levels of commenting. At compression time, users can add per-file comments, as well as one main comment for the entire Zip file. The per-file comments are usually used to give a short description of each file. The main comment is usually used for credits, copyright information, installation instructions, version numbers, etc. Pocket UnZip can display both types of comments.

Per-file comments can be viewed in Comments column of the main file list while in expanded mode (see the Zip File Listing section) and also in the properties dialog (see the Properties Dialog section).

The main Zip file comment can be viewed by selecting Zip File Comment from the View menu or by pressing the associated toolbar button. This option will be disabled if the Zip file does not contain a main comment.


Extracting Files

Once you have opened a Zip file into Pocket UnZip, you should see a list of the Zip file's contents. Select one or more files from the file list and then choose Extract Selected Files (Ctrl+E) or Extract All Files (Ctrl+A, Ctrl+E) from the Action menu. You may also use the noted shortcut keys or the associated toolbar buttons.

An extract options dialog will appear showing you some statistics about the files you are about to extract and prompting you for some information. There are three options available to you.

The Restore file paths option allows you to control whether the directory structure of the files you have selected to extract will be preserved. When this option is checked, any directory paths associated with the compressed files will be created, and the file will be extracted to the newly created directory. If this option is not checked, all files will be extracted to a single directory, regardless of any path information associated with the compressed files.

The Overwrite Options allow you to tell Pocket UnZip what to do if a file already exists on your file system with the same name of a file that is about to be extracted. The choices are:

The Extract To field specifies the root directory that should be used to extract files to. If you checked the Restore file paths option, then any directories associated with the files being extracted will be created under the directory specified in this field. The directory you enter must already exist. To create directories and browse for directories, use the Browse... button.

Once you have chosen the options you wish to use, press the Extract button. A progress dialog will appear and the extraction will begin. At any time during the extraction, you may tap the Abort button to abort the extraction operation.

Note: Aborting the extraction operation while processing a file will likely cause a partial file to get extracted and saved.

During the extraction, you may get interrupted for one of three reasons. First, if an error occurs, you will be notified with a message box. Second, if you have chosen the Prompt to overwrite option and you are trying to extract a file that already exists, you will be prompted on how to handle the situation. Third, if a file being extracted is encrypted, then you will be prompted for that file's password (see the Encrypted Files section).

Once the extraction is complete, the Abort button will change to a Close button and any errors or warnings will be displayed. Tap the Close button to return to Pocket UnZip's main screen.


Testing Files

Testing files is essentially the same as extracting files, except for that the actual extracted data is never written to your file system. Testing files is useful when you wish to verify the integrity of a Zip file without actually extracting the files within it.

Once you have opened a Zip file into Pocket UnZip, you should see a list of the Zip file's contents. Select one or more files from the file list and then choose Test Selected Files (Ctrl+T) or Test All Files (Ctrl+A, Ctrl+T) from the Action menu. You may also use the noted shortcut keys or the associated toolbar buttons.

A progress dialog will appear and the testing will begin. At any time during the testing, you may tap the Abort button to abort the testing operation.

During the testing, you may get interrupted for one of two reasons. First, if an error occurs, you will be notified with a message box. Second, if a file being tested is encrypted, then you will be prompted for that file's password (see the Encrypted Files section).

Once the testing is complete, the Abort button will change to a Close button and any errors or warnings will be displayed. Tap the Close button to return to Pocket UnZip's main screen.


Viewing Files

Pocket UnZip provides the ability to view, or even execute, files directly from a Zip file. This feature is a major convenience over having to extract and then manually open each file you wish to view. Internally, this is what Pocket UnZip is doing for you, but it takes care of all the work of extracting the file to a temporary directory, launching the associated viewer for that file type, and cleaning up when done.

To view a file, simply select a single file from Pocket UnZip's main file list and press Enter. You may also choose View Selected File from the Action menu, press the associated toolbar button, or just double-tap on the file you wish to view.

The file will be extracted to a directory called Temporary Pocket UnZip Files in the root of your file system. If the file you wish to view is encrypted, you will be prompted for a password. If the file has an associated viewer application installed (such as Pocket Word for .PWD files), then that viewer will automatically be launched with the newly extracted file as its command line. If there is no associated viewer application, then you will be prompted for the application you wish to use to view the file.

Pocket UnZip also provides minimal support for allowing you to use the view file action to run executable programs directly from the Zip file. If the file you choose to view is an executable (file extension is EXE), then the file will be executed after it is extracted. Pocket UnZip will only extract the file you select and none of its dependent files (like DLLs). If the executable you extract depends on other files in the Zip file, it will most likely fail to execute.

When Pocket UnZip exits, it will delete the Temporary Pocket UnZip Files directory and all the files in it. If you are running more than one instance of Pocket UnZip, then only the last instance of Pocket UnZip that you exit will perform this delete. Most applications, such as Pocket Word, lock files when viewing them. Any files being viewed by such an application when you exit Pocket UnZip will not be deleted.


Encrypted Files

If an encrypted file is encountered during an extract, test, or view operation, you will be prompted for a password. You can choose to skip the file, skip all encrypted files, or enter a password. You will be given three attempts at entering the correct password before the file will be skipped automatically. Once you have entered the correct password for a given file, that password will be remembered and automatically used for all other encrypted files that are encountered during that single extract, test, or view operation. If another encrypted file is found that uses a different password than the remembered password, then you will be prompted again for a new password.

This technique provides support for multi-password Zip files, while still providing users with single password Zip files the convenience of only having to enter their password once during the operation for all encrypted files. For security reasons, passwords are not remembered after the operation completes.


About Pocket UnZip

Thank you for using Version 1.0 of Pocket UnZip for Windows CE.

Pocket UnZip was developed by Steve P. Miller. Although I'd like to take full credit, I could not have done it without the public decompression source code provided by the Info-ZIP group. Pocket UnZip uses version 5.30 of Info-ZIP's core decompression code. Many thanks go to Greg Roelofs and all the fine folks at Info-ZIP.

Please send all comments, suggestions, and bug reports to stevemil@pobox.com.

Pocket UnZip is freeware - no shareware fees, no purchase fees. You can still send me an email or a box of cookies if you like it. If you would like to distribute Pocket UnZip, please contact me.

For the latest news, binaries, source code, and more information about the Info-ZIP group, visit http://www.cdrom.com/pub/infozip.

For more information about me, or to check out some of my other applications (mostly Windows 95 / NT / CE), stop by my personal web page at http://pobox.com/~stevemil/.

Copyright 1997 Steve P. Miller. All Rights Reserved.