tests the file access errors indicator
err = merror([fd]) [err, msg] = merror([fd])
a scalar: the fd
parameter returned by the
function mopen
is used as a file descriptor
(it's a positive integer). -1 stands for last opened file. The
default value is -1.
a scalar: an error status number of the most recent file I/O operation associated with the specified file.
If the most recent I/O operation performed on the specified
file was successful, the value of msg
is empty
and merror
returns an err
value of 0.
a string: an error string message.
The function merror
is used to test the file
access errors indicator returning non-zero if it is set. The error
indicator can only be reset by the mclearerr
function.
A nonzero err
indicates that an error occurred in the most recent file I/O operation. The value of message is a string that can contain information about the nature of the error. If the message is not helpful, consult the C run-time library manual for your host operating system for further details.