DOKK / manpages / debian 10 / libxt-dev / XtError.3.en
XtError(3) XT COMPATIBILITY FUNCTIONS XtError(3)

XtError, XtSetErrorHandler, XtSetWarningHandler, XtWarning - low-level error handlers

void XtError(String message);

void XtSetErrorHandler(XtErrorHandler handler):

void XtSetWarningHandler(XtErrorHandler handler);

void XtWarning(String message);

Specifies the nonfatal error message that is to be reported.
Specifies the new fatal error procedure, which should not return, or the nonfatal error procedure, which usually returns.
Specifies the message that is to be reported.

The XtError function has been superceded by XtAppError.

The XtSetErrorHandler function has been superceded by XtAppSetErrorHandler.

The XtSetWarningHandler function has been superceded by XtAppSetWarningHandler.

The XtWarning function has been superceded by XtAppWarning.

XtAppError(3)
X Toolkit Intrinsics - C Language Interface
Xlib - C Language X Interface

libXt 1.1.5 X Version 11