Ok, I've checked this with gfix version: gfix version WI-V2.5.1.26351 Firebird 2.5

According to stackoverflow: I can test the error result of application like this: http://stackoverflow.com/questions/3452046/get-error-code-from-within-a-batch-file

So I did a batch file and executed it:

C:\Program Files (x86)\Firebird\Firebird_2_5\bin>gfix -validate "C:\Program Files (x86)\Firebird\Firebird_2_5\bin\MYBASE-3334.FDB" -user SYSDBA -password masterkey -no_update && echo Done!
Summary of validation errors
Number of database page errors : 17
Done!


As you see, even with errors in database gfix will return me errorcode = 0.

So as far as I see it, there is no reliable way to tell programmatically whether gfix detected error or not.

Best regards.