syspath_once

Controls how included files are treated when #pragmaonce is enabled.

Syntax

#pragma syspath_once on | off | reset

Remarks

When this pragma and pragma once are set to on , the compiler distinguishes between identically-named header files referred to in

#include < 
file-name 
>

and

#include " 
file-name 
" .

When this pragma is off and pragma once is on , the compiler will ignore a file that uses a

#include <file-name>

directive if it has previously encountered another directive of the form

#include "file-name"

for an identically-named header file.

shows an example.

This pragma does not correspond to any panel setting. By default, this setting is on .

Listing 1. Pragma syspath_once example

#pragma syspath_once off
#pragma once on /* Include all subsequent files only once. */
#include "sock.h"
#include <sock.h> /* Skipped because syspath_once is off. */