Debugging Storyboard IO

Debugging egress (Storyboard Engine sending to backend)

Table 5. No events are being received

Possible Issue


Receive channel is not open

Launch Storyboard engine with verbosity (-v) and you see the following warning on sending an event WARN [0.135]:Can't open greio channel channel_name , then the channel is not open. If receiver is in C code ensure the gre_io_open returned successfully. If communicating with another Storyboard application ensure the receiving application was launched with the expected channel name specified with command line parameter -ogreio,channel=channel_name

Channel name mismatch

If there is a mismatch on channel name you will not receive messages. One way to verify is to stop the receiver and use utility iorcv. Just launch iorcv with the same channel name as your receiver: ./iorcv [-s] channel_name

System Permissions

On some systems, system permissions can block the IO communications. Try running with administrator privileges, if the above steps have not resolved the issue. You can use iogen and iorcv to verify permissions.

Table 6. A particular event is not being received

Possible Issue


event not sent

Launch Storyboard Engine with verbosity level 4 (-vvvv). Verify in the log that the action or Lua code to trigger the event was executed. If you see WARN [0.135]:Can't open greio channel and you have already verified channel is open, then verify the channel name is correct in send event call

Event not received

Most common scenario is a event name mismatch. Using iorcv you can verify the name that is being sent, ensure it matches what the receiver expects.

Table 7. Event data not correct

Possible Issue


Format string not correct

If the data values are not received as expected it likely the format string either does not match the data. Ensure the format size matches the size of the data. If specifying a name to the parameter ensure the names are the same.

Data not aligned.

Data must be aligned to system data alignment. Particular problem sizes are 1u1, 1s1, 1s0 (strings). Data must be sent in order of descending alignment requirements. Example: 4u1 4u1 2u1 1s0 is good, 2u1 4u1 4u1 1s0 is not

Debugging ingress (Storyboard Engine receiving from backend)

Table 8. The trouble shooting steps for egress Storyboard apply in this scenario, so see the above steps.



Event not received

Launch Storyboard Engine with verbosity level 4 (-vvvv) you will see the following event trace if successful. EVENT [111.811]:GREIO received event [MilleniumFalconSpeed] 2 bytes EVENT [111.811]:IO: Queue [1] MilleniumFalconSpeed EVENT [111.811]:IO: Dispatch [MilleniumFalconSpeed] ACTION [111.811]:ACTION: Invoke [MilleniumFalconSpeed]->[gra.lua] on app [app] If the last two messages are not displayed Storyboard received the event but could not find a handler for the event.

Was this article helpful?
0 out of 0 found this helpful