comedi_errno — number of last Comedilib error


#include <comedilib.h>
int comedi_errno(void); 


When a Comedilib function fails, it usually returns -1 or NULL, depending on the return type. An internal library variable stores an error number, which can be retrieved by calling comedi_errno This error number can be converted to a human-readable form by the functions comedi_perror and comedi_strerror.

These functions are intended to mimic the behavior of the standard C library functions perror, strerror, and errno. In particular, Comedilib functions sometimes return an error that is generated inside the C library; the comedi error message in this case is the same as the C library.

The function comedi_errno returns an integer describing the most recent Comedilib error. This integer may be used as the errnum parameter for comedi_strerror.