How to find out why an app quits after starting?

This one was fixed by compiling on a Linux machine, in 2017R3. None of the 2018 versions worked (either linux or windows) and 2019R1 did not work either on linux or windows!

There really should be some fix to this. There is no indication of why it crashes in any logs. Since it works in some versions of Xojo, and compiled on Linux Vs Windows there must be something that Xojo can do to fix this, and to at least advise to the logs why it crashed!

Very very frustrating and a huge waste of time!
Tim

File a feedback report with a sample project.

[quote=432294:@Tim Seyfarth]This one was fixed by compiling on a Linux machine, in 2017R3. None of the 2018 versions worked (either linux or windows) and 2019R1 did not work either on linux or windows!

There really should be some fix to this. There is no indication of why it crashes in any logs. Since it works in some versions of Xojo, and compiled on Linux Vs Windows there must be something that Xojo can do to fix this, and to at least advise to the logs why it crashed!

Very very frustrating and a huge waste of time!
Tim[/quote]
If it’s working when built with 2017r3 and not with 2018r1, make sure you have the libunwind8 dependency (which was new in 2018r1) installed.

Hi Greg
libunwind8 is already installed and is the latest version.

As it stands right now, of the 3 apps I have in the pi, 2 of them are Console apps requiring compiling on a Linux PC (instead of my standard win10 PC) and will only run without quitting unexplainably, without warning or entries to any log including the system/syslog when compiled with 2017R3.

The third app is a Standalone web app, that also requires it to be compiled on a Linux PC, but appears to run just fine when compiled with the latest Xojo release 2019R1.

I could send the smallest of the console apps if that would help to get this resolved…

Also, you stated that a standalone web app will shut down if the port is in use. Does it output anything to the sys log? Since this is done by the framework(?) I would think there would be some type of messaging that would take place.

Thanks for the help!
Tim

In a Terminal, try launching one of the console apps using ldd. It may give us more info.

ldd yourAppName

@Tim Seyfarth , I wrote a little blog post on my site that gives some very basic ideas to get more info when your app crashes before Xojo can tell you what happened.
Debugging The Undebuggable
gdb is a good way to get crash info on Linux. pi should have it installed by default, I think.

@ Gregg - have not had time to go an create the non working files upload etc then run as you suggest to get the output. When I get a chance, I will - I need these things fixed as do others I am sure…

@ Jim - Thank you. When I get a spare moment, I will use your techniques. I did get it figured out in terms of which Xojo version and on WHAT OS it is compiled on to make it work. Wasted SO much time… But I suppose it is worth it if Xojo will review the findings too and make the changes on their end to make the compiled app behave properly on their later releases!

Again, much appreciated both of you! Will review and advise - probably will have questions too!
Tim

Tim - one more thing to keep in mind - Linux will hold a port for about 30-45 seconds after it is closed as a mechanism to prevent port spamming. Make sure that you are waiting at least a minute before you try to launch the new copy.