# Select Data Source

> [HTML Version](selectdatasource.htm)

**xcall AUI, AUI\_IMAGE, IMGOP\_SELECTSRC, handle, status \{,sourcename\}**

IMGOP\_SELECTSRC allows you to specify which of the available TWAIN data sources (input devices) is to be used for subsequent "Acquire" operations. If _sourcename _is specified and non-blank, it will attempt to select the corresponding data source from among the available options. Otherwise it will pop up a dialog box allowing the user to select from among the available data sources. 

This operation (with no _sourcename_) should be exactly equivalent to the "Select Source" menu option that appears on the File menu of most programs that support TWAIN.