https://invisible-island.net/xterm/xtoolkit/
XtErrorMsg, XtSetErrorMsgHandler, XtWarningMsg, XtSetWarningMsgHandler - high-level error handlers
#include <X11/Intrinsic.h> _X_NORETURN void XtErrorMsg(const char *name, const char *type, const char *class, const char *defaultMsg, String *params, Cardinal *num_params); void XtSetErrorMsgHandler(_X_NORETURN XtErrorMsgHandler msg_handler); void XtSetWarningMsgHandler(XtErrorMsgHandler msg_handler); void XtWarningMsg(const char *name, const char *type, const char *class, const char *defaultMsg, String *params, Cardinal *num_params);
class Specifies the resource class of the error message. default Specifies the default message to use. name Specifies the general kind of error. type Specifies the detailed name of the error. msg_handler Specifies the new fatal error procedure, which should not re- turn or the nonfatal error procedure, which usually returns. num_params Specifies the number of values in the parameter list. params Specifies a pointer to a list of values to be stored in the message.
The XtErrorMsg function has been superseded by XtAppErrorMsg. The XtSetErrorMsgHandler function has been superseded by XtAppSetEr- rorMsgHandler. The XtSetWarningMsgHandler function has been superseded by XtAppSet- WarningMsgHandler. The XtWarningMsg function has been superseded by XtAppWarningMsg
XtAppErrorMsg(3) X Toolkit Intrinsics - C Language Interface Xlib - C Language X Interface X Version 11 libXt 1.3.1 XtErrorMsg(3)