LinuxRT Network Communication Causes Error 11

Updated Apr 18, 2025

Issue Details

I am running a program for network communication on Linux RT. When trying to open a file in another process of the VI, error 11 occurs. Additionally, the process for blinking an LED sometimes stops.

Solution

In Linux, there is a limit on the number of file descriptors (identifiers for opening files) that a single process can open simultaneously. By default, this limit is set to 1024. This count is shared with the number of network sockets. In other words, if too many network sockets are opened, there is a risk that files cannot be opened. The function that blinks the LED internally performs file open and close operations. This causes the blinking to stop.

The increase in the number of network sockets can be due to a high number of connections or, in some cases, the number may increase due to reconnections caused by errors. This may occur, for example, if the port numbers used by LabVIEW are duplicated.

To resolve this issue, either close files frequently or ensure that the number of network sockets does not become too large. Pay special attention to avoiding duplication of port numbers used by LabVIEW. For information on the port numbers used by LabVIEW, please refer to the related link "Configuring Software and Hardware Firewalls to Support NI Products."