> -----Original Message----- > From: development-bounces+kai.koehne=digia....@qt-project.org > [...] > Here's what I propose: > > Heuristically determine at runtime. On all platforms (including Windows), use > only the fact that a terminal is present. If a terminal is present, write to > it > using stderr. Otherwise, write to the system log. > > * Implications for Qt Creator: > 1) it must be able to read from the system log for desktop debugging > (especially when running applications without "Run in terminal"). That's > already done on Windows. It will be necessary to add support for journald > (Linux) and asl (OS X).
Well, actually your latest patch that checks for "stderr!=/dev/null" will just work fine with current Qt Creator. That's for journal/Linux at least, haven't had a look yet how asl works. Qt Creator needs to continue listening to stderr in any case: You still want to see stdout/stderr, after all. It's true that Qt Creator can in theory profit from additional information piped through systemd, but integrating both streams also has it's issues: E.g. the order of qDebug/stderr messages is no longer consistent, and interleaving lines might need special attention (though I guess we handle that already for stdout/stderr). > 2) remote debugging: per platform, it needs to be decided whether we can > access the log on the remote device. If so, that's the best situation. If it > isn't, > then we need to force Qt to log to stderr. > > 2a) set QT_LOGGING_TO_CONSOLE=1 in the environment > 2b) force the allocation of a terminal (if using ssh, pass the -t option) See above. Unless stderr somehow ends up in the system log too we need to anyway have the terminal. > I recommend advising Linux distributions to disable journald logging at least > until Creator is updated. And the support for asl on OSX should be held until > the same time. I agree (though I'm not sure whether Qt Creator is the blocker, or if it's enough to handle the issue in Qt. See above). > * Implications for unit tests: > Except for the unit tests testing logging to the system log in the first > place, > QT_LOGGING_TO_CONSOLE=1 should be set. I think QtTest itself should do > that. > > * Support for journald in the pre-built Creator binary: > 1) new plugin, link to libsystemd-journal.so.0. If the library isn't present > in the > target system, the plugin won't load. > > 2) dlopen libsystemd-journal.so.0. If it isn't present, then Qt can't very > well > be logging to it. > > 3) use QProcess to run journalctl -f > > * Support for journald in the pre-built Qt binaries: > Disabled. > -- > Thiago Macieira - thiago.macieira (AT) intel.com > Software Architect - Intel Open Source Technology Center > > _______________________________________________ > Development mailing list > Development@qt-project.org > http://lists.qt-project.org/mailman/listinfo/development _______________________________________________ Development mailing list Development@qt-project.org http://lists.qt-project.org/mailman/listinfo/development
