Using command line utilties and checking the resultant exit code

Problem: When using the InterBase utilities in a batch file the exit status of the InterBase utilities needs to be checked. Solution: When writing a batch script on NT or Win95 there is a batch construct to handle checking of exit status codes. To check the status code use the construct: if errorlevel x where x is the errorlevel you want to check for. This statement will return true if the exit code is greater than or equal to the number specified. If the errorlevel is >= to the specified number the specified command will be executed. This command can include printing of error messages or exiting the batch file. Here is an example script to perform a gbak and print an error message if gbak was unsuccessful: @echo off echo "file to gbak is: " gbak -z -b %1 %2 if errorlevel 1 echo "errorlevel 1" ------------------------------- end script ----------------------------------- The @echo off prevents all commands from being echoed to the screen, %1 and %2 are the first 2 command line parameters. In this case they represent the database to be backed up and the filename to backup to. The if statement after the gbak will check to see if the exit code is >= 1 and if it is, print an error message. An exit code of 0 means success and an exit code of 1 means failure, as defined in common.h.