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Top Forums Programming Trivial doubt about C function pointer Post 302548275 by royalibrahim on Thursday 18th of August 2011 02:45:43 AM
Old 08-18-2011
Trivial doubt about C function pointer

Hi,

In the below C code,
Code:
#include <stdio.h>

void print() {
    printf("Hello\n");
}

int main() {
   void (*f)() = (void (*)()) print;
   f();   
   (*f)();
}

I wonder, how the syntaxes "f()" and "(*f)()" are treated as same without any error? Is this an improvement or ANSI/ISO standard?
 

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XmScrollVisible(library call)											     XmScrollVisible(library call)

NAME
XmScrollVisible -- A ScrolledWindow function that makes an invisible descendant of a ScrolledWindow work area visible SYNOPSIS
#include <Xm/ScrolledW.h> void XmScrollVisible( Widget scrollw_widget, Widget widget, Dimension left_right_margin, Dimension top_bottom_margin); DESCRIPTION
XmScrollVisible makes an obscured or partially obscured widget or gadget descendant of a ScrolledWindow work area visible. The function re- positions the work area and sets the specified margins between the widget and the nearest viewport boundary. The widget's location relative to the viewport determines whether one or both of the margins must be adjusted. This function requires that the XmNscrollingPolicy of the ScrolledWindow widget be set to XmAUTOMATIC. scrollw_widget Specifies the ID of the ScrolledWindow widget whose work area window contains an obscured descendant. widget Specifies the ID of the widget to be made visible. left_right_margin Specifies the margin to establish between the left or right edge of the widget and the associated edge of the viewport. This margin is established only if the widget must be moved horizontally to make it visible. top_bottom_margin Specifies the margin to establish between the top or bottom edge of the widget and the associated edge of the viewport. This margin is established only if the widget must be moved vertically to make it visible. For a complete definition of ScrolledWindow and its associated resources, see XmScrolledWindow(3) RELATED
XmScrolledWindow(3). XmScrollVisible(library call)
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