I'm stuck. I try to open a serial Port on Linux using Pharo. The code is as simple as: port := SerialPort new. portName := '/dev/ttyUSB0'. port openPort: portName. Now this opening fails for "whatever" reason. Anyway in the console I got the following "messages": PluggableTextMorph>>handleEdit: in Block: [result := editBlock value] Error while opening the serial port (/dev/ttyUSB0#4 ). Error: Cannot open '/dev/ttyUSB0' It seems after the USB0 there is not the "end" of the string but some gibberish. I tried to extract the code for the SerialPlugin and use it stand-alone in C andwrote the following: #include <stdio.h> #include "SerialPlugin.h" int main(void) { char *portName = "/dev/ttyUSB0"; int baudRate = 9600; int stopBitsType = 1; int parityType = 0; int dataBits = 8; int inFlowControlType = 0; int outFlowControlType = 0; int xOnByte = 19; int xOffByte = 24; int iRval; iRval = serialPortOpenByName (portName, baudRate, stopBitsType, parityType, dataBits, inFlowControlType, outFlowControlType, xOnByte, xOffByte); iRval = serialPortCloseByName (portName); return 0; } And there is no error while using it this way in C. So what is broken? Regards Friedrich