SAP Sybase IQ provides extensive logging and tracing capabilities. UDFs should provide the same or better level of detailed logging, in the event of problems in the UDF code.
Log files for the database are generally located with the database file and configuration file. On UNIX platforms, there are two files named after the database instance, one with a .stderr extension and one with a .stdout extension. On Windows, by default, the stderr file is not generated.
iqsrv16.exe @iqdemo.cfg iqdemo.db 2>&1 > iqdemo.stdout
The Windows output messages are slightly different from the output messages generated on UNIX platforms.