Run on boot, receiving exit status of last run

Ward

Hey so I'm running my application on boot and when I start my application, I want to know if this is the first time running since boot, or if it is not, what the exit code of last time running is.

When starting an application I want to execute stuff based on if it crashed or gracefully exited

Is this possible?

I thought maybe the exit code of last run can be passed along as argument for next run, but I'm not sure where the exit code ends up, and how to add the exit code to the CLI options, and have that enter my program in setup().

I also though in the event that I gracefully exit from the application (by calling Bela_requestStop()) I can have the cleanup() write or even just touch a file to to signify the program exit was intended, but ideally I wouldn't want to do file i/o in the cleanup.

giuliomoro

if you create a file in /opt/Bela/local/bela_startup.sh (and make it executable), it will be called at boot with the PROJECT and ARGS (and I think BELA_HOME) variables set. You can then use it to call your file:

#!/bin/bash

cd $BELA_HOME/projects/$PROJECT
while sleep 0.1; do
  LAST=$?
  ./$PROJECT $ARGS -f $LAST
done

where $? contains the exit code of the last command. To retrieve the value of the command-line option -f you should use provide a main.cpp file and use a procedure similar to the one used in, e.g.: example Extras/userData, to parse that variable in main() and pass it to setup() (and render() and cleanup()) via the void* userData pointer. Alternatively, easier but less elegant, you can set an environment variable before calling the program and access it via getenv(), e.g.:

#!/bin/bash

cd $BELA_HOME/projects/$PROJECT
while sleep 0.1; do
  export LAST=$?
  ./$PROJECT $ARGS
done

then in C++ (untested):

// at the top
#include <stdlibg.h>
...
//  in setup()
int last = 0; // default value if LAST is not defined
const char* lastStr = getenv("LAST");
if(lastStr)
  last = atoi(lastStr);