Display error message with identifier and return to MATLAB prompt
#include "mex.h" void mexErrMsgIdAndTxt(const char *errorid, const char *errormsg, ...);
#include "fintrf.h" subroutine mexErrMsgIdAndTxt(errorid, errormsg) character*(*) errorid, errormsg
erroridString containing a MATLAB® message identifier. For information on creating identifiers,
see MException.
errormsgString to display, specified as const char*
in C or character*(*) in Fortran. In C, the function supports either UTF-8 or
local code page (LCP) encoding and the string can include conversion specifications, used by the
ANSI® C
printf function. The encoding for both the message text and the conversion
arguments must be the same.
...In C, any arguments used in the message. Each argument must
have a corresponding conversion specification. Refer to your C documentation
for printf conversion tables.
The mexErrMsgIdAndTxt function writes an error message to the
MATLAB window. For more information, see the error function syntax statement using a message identifier. After the
error message prints, MATLAB terminates the MEX file and returns control to the MATLAB prompt.
Calling mexErrMsgIdAndTxt does not clear the MEX file from
memory. So, mexErrMsgIdAndTxt does not invoke the function
registered through mexAtExit.
If your application called mxCalloc or one of the
mxCreate* routines to allocate memory,
mexErrMsgIdAndTxt automatically frees the allocated
memory.
Note
If you get warnings when using mexErrMsgIdAndTxt, you might
have a memory management compatibility problem. For more information, see Memory Management Issues.
In addition to the errorid and errormsg, the
mexErrMsgIdAndTxt function determines where the error occurred,
and displays the following information. For example, in the function
foo, mexErrMsgIdAndTxt displays:
Error using foo
If you compile your MEX file with the MinGW-w64 compiler, see the limitations with exception handling topic in Troubleshooting and Limitations Compiling C/C++ MEX Files with MinGW-w64.
See these examples in
matlabroot/extern/examples/refbook
char InputThe following code snippet checks if input argument, prhs[0],
is a string. If not, the code displays a warning. If there is an error reading the
input string, the code displays an error message and terminates the MEX file.
char *buf;
int buflen;
// initialize variables
if (mxIsChar(prhs[0])) {
if (mxGetString(prhs[0], buf, buflen) == 0) {
mexPrintf("The input string is: %s\n", buf);
}
else {
mexErrMsgIdAndTxt("MyProg:ConvertString",
"Could not convert string data.");
// exit MEX file
}
}
else {
mexWarnMsgIdAndTxt("MyProg:InputString",
"Input should be a string to print properly.");
}
// continue with processing