To start the X Window interface to Interchange for SGI IRIX, enter 'icx'. If the installation directory is not on your current path for searching for programs, you can specify the full path or add the Interchange directory to your path. If you are familiar with the interface of Interchange for Microsoft Windows, the X Window Motif interface should be quite familiar.

For more information about the 'icx' user interface, see the descriptions of Interchange for Windows. The user interface is almost the same.

Command line interface
Interchange for SGI IRIX also includes an alternative interface called 'iccli' that does not use the X Window Motif graphical user interface of the 'icx' program. This interface is not present in the Microsoft Windows version of Interchange.

This command-line interface can be used to quickly convert files if you are accustomed to the Unix shell or prefer to carry out conversions using shell scripts.

Depending on the types of conversions you need, you may choose the graphical interface or the command line interface. The command line interface can be used within your own shell scripts, making it possible to automate more complex conversions than the single batch conversions of the graphical interface.

The 'iccli' interface allows both batch and simple single conversions.

Simple conversion
This command converts a single 3D Studio file to stereolithography format:

iccli chevy.3ds "stereolithography asc"   

Interchange will examine the contents of the source file "chevy.3ds" and attempt to automatically determine its file format. There is no need to tell Interchange what type of data is stored there.

The second (or in general, last) argument sets the export format. In this example, the "stereolithography asc" format chooses the ASCII version of that file format. This string can be any unambigious sub-string from the list of file formats available for export from Interchange.

For a definitive list of the acceptable file formats, enter just 'iccli' to see the usage. For some formats, the description can be very short, such as "byu". In other cases, the unabiguous description is longer, and needs to be enclosed in quotes if the description includes spaces.

During a command-line conversion, Interchange's status messages go to 'stderr' and can be redirected to a file with ">&".

Batch conversion
This command converts many 3D Studio files to Wavefront format:

iccli *.3ds "wavefront object"   

Your command shell expands the "*.3ds" to the filenames of all the files ending in ".3ds" in the current directory. For example, if the current directory only contained three files, you could also enter:

iccli chevy.3ds ford.3ds volvo.3ds "wavefront object"

If there were no "*.3ds" files in the current directory, the error message is:

iccli: No match.

Dialog for conversion options
Even with the command line interface, you can invoke the options dialog for either the importing or the exporting Converter. This command converts many 3D Studio files to Wavefront format:

iccli chevy.3ds -d "wavefront object"      

The "-d" option follows the file specification of the Converter you want to invoke. In the example above, the "-d" follows "chevy.3ds", so the 3D Studio Converter's dialog will open before this file is imported. You can adjust the Converter's options. When you close this option dialog, the conversion continues. To invoke the Wavefront Converter's dialog, you'd enter the "-d" at the end of the above command line.

Command line conversion options
All Interchange Converters have option dialogs. These dialogs present a user interface to settings that control the way files are imported or exported in that format. For more information about options files, see the following chapter. These option settings are persistent between sessions. The next time you run Interchange, the values will be the same as your last session.

You can adjust the conversion options from the command line. This method is arcane and inconvenient for most casual use, but it is a feature for people writing scripts to drive complicated conversions.

It uses the key-value pairs found in each Converter's "INI" file. For example, to turn on "lone edges" and turn off "lonepoints" in the Wavefront Converter, you can enter:

iccli *.3ds "wavefront object" -doLoneEdges=0 -doLonePts=1

Changing settings on an option dialog makes permanent changes in the options file, as described in a section below.

Recognizing files
The command line interface also offers a convenient method of identifying the types of files, similar to the Unix 'file' command.
This command will display the type of every file in the current directory, as recognized by Interchange:

iccli -g *

Options files
In Interchange for SGI IRIX, the settings in the Options dialogs for Interchange and its Converters are stored in files ending in ".INI". These files are stored in a directory called '.Interchange' (dot Interchange) in the user's home directory. This allows each user of Interchange to maintain their own settings.

Alternatively, the environment variable 'IC_HOME' is used to specify a directory where the option files will be kept. If for some reason the '.Interchange' or 'IC_HOME' directories cannot be used, the option files will be created in the directory where the Interchange executable itself is located.

Within the option files, options are in the form of "key" and "value" pairs, separated by an equal character, where the key is a keyword such as "doLoneEdges" similar to the descriptive text found on the Options dialog, and value is a numeric or string value reflecting the setting. Simple "on" and "off" values are represented with '0' and '1', respectively.

For example, here is the contents of the default "WAVE.INI" file for the Wavefront Converter, showing the keyword and value pairs.

[Preferences]
doLonePts=0
doLoneEdges=0
doOrigFaces=1
doOppFaces=0
doMatLib=0
doShortMats=1
doRewind=1
EndingState=1