How can I open a .alx or .cod or .prc or .sis file on a computer?

Question

I found a .zip file of something, and I downloaded it. Inside it were only a .alx and a .cod file (presumably of the same thing). I don't have a Blackberry. Is there a way to open one of the two of them on a computer (Windows 7)? I also found .prc and .sis versions of the same thing.

This file contains text, so I am looking for a way to get the text inside it. I don't know what (if any) interface is before the text. I am looking for something like Ibis Reader.

Answer 1

These file types are associated with apps for various mobile devices (e.g. Blackberry Java apps). Since these are generally undocumented proprietary compiled formats, they will probably be of little use to you unless you want to reverse-engineer the app. If you do, patience, trial and error, and a hex editor will be needed.

In general, for unknown package formats it's useful to try opening in 7-zip. It's possible that the archive contains files in some e-book format you can read.

alx

From here, we see that an alx file is an XML document containing a description of the app, e.g.

<loader version="1.0">
     <application id="com.rim.samples.device.httpdemo">
          <name>Sample Network Application</name>
          <description>
               Retrieves a sample page over HTTP connection.
          </description>
          <version>1.0</version>
          <vendor>Research In Motion</vendor>
<!-- more metadata truncated -->
     </application>
</loader>

You can therefore open it in any text editor, e.g. MS Notepad or Notepad++.

cod

A cod file is apparently a proprietary encoding of a compiled Java class file. This guy has reverse-engineered the format's header. With some effort you could probably extract the Java bytecode, and then disassemble it using javap. But unless you're interested in reverse-engineering the app, this file probably won't be of any use to you.

prc

I believe this is a Palm Pilot code format. See whether you can find Palm-related computer software that can read it. If it's just an app, it will probably be of little use to you for the same reason as for cod.

However, it's also been extended into an e-book format, so you could try opening it in an e-book reader like Calibre if you suspect that's what it contains.

sis

As Journeyman Geek pointed out, SIS is an installer package for Nokia/Symbian devices. It might be a renamed ZIP file (try opening it in 7-zip). Since Symbian is partly open-source, you might be able to find better docs for this format.

Answer 2

Use a text editor like Notepad++. If that doesn't show anything that makes sense, try using a hexeditor plugin with it and see if that works. You can cut your text out of the files.

To install the HEX Editor plugin, just extract the HexEditor.dll file from the downloaded ZIP file, and copy it to Notepad++\plugins folder, i.e. C:\Program Files\Notepad++\plugins or C:\Program Files (x86)\Notepad++\plugins.

Answer 3

If you have access to a Linux system, you should use the builtin utility named 'file' that guesses the file types based on many different informations, which can give you precious clues on what to do with them. Or sometimes not: if it tells you it's a Berkeley DB that won't tell you what can usefully open it.

To use it, in a terminal, type:

# file filename1.alx filename2.cod

If you have no easy access to a Linux system, try downloading it for windows on http://gnuwin32.sourceforge.net/packages/file.htm (usage will be the same)

Finally, there are online services that can help you, like http://filext.com/file-extension/COD