RAPID reference manual - Technology

InstructionOpenDirFile and Serial Channel HandlingOpenDir - Open a directoryOpenDir is used to open a directory for further investigation.ExamplePROC lsdir(string dirname)VAR dir directory;VAR string filename;OpenDir directory, dirname;WHILE ReadDir(directory, filename) DOTPWrite filename;ENDWHILECloseDir directory;ENDPROCThis example prints out the names of all files or subdirectories under the specifieddirectory.ArgumentsOpenDirDev PathDevData type: dirA variable with reference to the directory, fetch by OpenDir.This variable is then used for reading from the directory.PathData type: stringPath to the directory.LimitationsOpen directories should always be closed by the user after reading (instruction CloseDir).Error handlingIf the path points to a not existing directory or if there are too many directories open atthe same time, the system variable ERRNO is set to ERR_FILEACC. This error canthen be handled in the error handler.RAPID reference manual - part 1a, Instructions A-R 311