so if I understand an summarize correctly we'd change - the usage() for all to return 1 - print messages on exceptions to System.err - rethrow the exception so java can handle it if it will terminate afterwards anyway - use something above 2 and below 126 as an error code for System.exit() if rethrowing doesn't make sense
OK? Maruan Am 15.01.2015 um 19:03 schrieb John Hewson <j...@jahewson.com>: > If the usage was printed due to invalid command line parameters, then the > convention on Unix is to return exit code 1. We should be doing that too. > > Note than if Java throws an exception which causes main() to exit and there > is no catch clause, then java will return a non-zero code of its own accord. > If we’re catching fatal exceptions in main, then we should System.exit(1) > afterwards. > > -- John > >> On 15 Jan 2015, at 09:13, Maruan Sahyoun <sahy...@fileaffairs.de> wrote: >> >> Yes, >> >> current behavior within the tools >> usage(): some tools have a System.exit, some don't and for the ones they >> have the exit code is not always the same. >> -main() there is no System.exit for the ones I looked at in case of an >> error. Only an error message is written to System.err >> >> You'd rather expect System.exit > 0 in case there is an issue in main >> processing and then System.exit as part of usage makes sense. If there is >> none on main there shouldn't be one on usage(). >> >> So I'd remove it on usage() too. >> >> WDYT? >> >> Maruan >> >> Am 15.01.2015 um 18:00 schrieb Andreas Lehmkuehler <andr...@lehmi.de>: >> >>> Hi, >>> >>> Am 15.01.2015 um 17:20 schrieb John Hewson: >>>> Only if there's a non-zero number used as the argument. >>> Yes, but IMO such a value is only useful if there is any processing issue. >>> Maruans question targets those calls within the usage message which is >>> shown only if there is any issue with the given commandline parameters. >>> >>> I'd remove such calls. >>> >>>> -- John >>>> >>>>> On 15 Jan 2015, at 06:06, Maruan Sahyoun <sahy...@fileaffairs.de> wrote: >>>>> >>>>> Hi, >>>>> >>>>> do we need System.exit() in our command line tools usage messages? >>>>> Opinions? Don't see a benefit of having them. >>>>> >>>>> BR >>>>> Maruan >>> >>> BR >>> Andreas LEhmkühler >> >
