On macOS, you can enable tracing through the Tracing tab of the iODBC Data Source Administrator.
To specify the path and name of the trace log file, type the path and name in the Log file path field or click Browse to select a log file. If no location is specified, the trace log resides in the working directory of the application you are using.
The iODBC Data Source Administrator ships with a trace library that is enabled by default. If you want to use a custom library instead, type the path and name of the library in the Custom trace library field or click Browse to select the library.
To enable tracing, indicate the frequency of tracing for the "When to trace" option on the Trace tab. If you select All the time, tracing continues until you disable it. Be sure to turn off tracing when you are finished reproducing the issue because tracing decreases the performance of your ODBC application.
After making changes on the Tracing tab, click Apply for them to take effect.
The DataDirect enhanced tracing library gives you more control over tracing. See "System Information (odbc.ini) File" for a complete discussion of how to configure enhanced tracing.