Error messages and the output of the display command are always sent to standard output and will trigger responses in your ESL program.  The SQL Executable sends any error messages that result from the use of invalid command line arguments (in the start local command) to the errorlog. No ESL responses will be generated for these.

The ESL SQL Executable generates error strings and/or error codes when an error is detected. Some errors are detected by the SQL Executable directly, and some are detected by the database server.

If the error is detected by the SQL Executable (such errors include direct, configuration, and some inquiry command errors), it returns a single line, beginning with the configured error string and containing a description of the error. This line is followed by the prompt string. For example, if you issue a startdb command with no database name, you receive the following error:

ERROR: syntax error in startdb command SQL> 

If the error is detected by the database server, one or more additional lines of error messages may be delivered if the verbose on command has been issued. These additional lines are delivered before the SQL Executable's error message; they usually contain useful information about the reason for the error.

Using the verbose on option is recommended only during program development.