comedi_perror — print a Comedilib error message
#include <comedilib.h>
void comedi_perror( | const char * s); |
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 with
comedi_errno.
This error number can be converted to a
human-readable form by the functions
comedi_perror or
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_perror prints an error message to
the standard error output stream stderr.
The error message consists of the argument string
s, a colon, a
space, a description of the error condition, and a new line.