Query the error status of the stream specified by file descriptor fid
If an error condition exists then return a string msg describing the
error. Otherwise, return an empty string ""
.
The second input "clear"
is optional. If supplied, the error
state on the stream will be cleared.
The optional second output is a numeric indication of the error status. err is 1 if an error condition has been encountered and 0 otherwise.
Note that ferror
indicates if an error has already occurred, not
whether the next operation will result in an error condition.
See also: fclear, fopen.
Package: octave