Specifies the I/O return codes that will make the IF condition true. If any one of the I/O codes matches the I/O return code of the last I/O operation then the IF statement is deemed to be "true".
Specifies the I/O return codes that will make the IF condition true in negation. If any one of the I/O codes does not match the I/O return code of the last I/O operation then the IF statement is deemed to be "true".