int comedi_command_test (comedi_t * device, comedi_cmd * command);
The function comedi_command_test() tests the command structure pointed to by the parameter command and returns an integer describing the testing stages that were sucessfully passed. In addition, if elements of the command structure are invalid, they may be modified. Source elements are modified to remove invalid source triggers. Argument elements are adjusted or rounded to the nearest valid value.
The meanings of the return value are as follows.
0 indicates a valid command.
1 indicates that one of the *_src members of the command contained an unsupported trigger. The bits corresponding to the unsupported triggers are zeroed.
2 indicates that the particular combination of *_src settings is not supported by the driver, or that one of the *_src members has the bit corresponding to multiple trigger sources set at the same time.
3 indicates that one of the *_arg members of the command is set outside the range of allowable values. For instance, an argument for a TRIG_TIMER source which exceeds the board's maximum speed. The invalid *_arg members will be adjusted to valid values.
4 indicates that one of the *_arg members required adjustment. For instance, the argument of a TRIG_TIMER source may have been rounded to the nearest timing period supported by the board.
5 indicates that some aspect of the command's chanlist is unsupported by the board. For example, some board's require that all channels in the chanlist use the same range.