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Using the hdrstop Pragma

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The hdrstop pragma gives you additional control over precompilation filenames and over the place at which the compilation state is saved. The syntax of the hdrstop pragma is

#pragma hdrstop ("filename")

where filename is the name of the precompiled header file to use or create (depending on whether /Yu or /Yc is specified). If the filename does not contain a path specification, the precompiled header file is assumed to be in the current directory. Any filename is ignored when the automatic precompiled header option (/YX) is specified.

Note   The hdrstop pragma is ignored unless either the /YX option is specified or the /Yu or /Yc compiler option is specified without a filename.

For the /Yc and /Yu options, if neither of the two compilation options nor the hdrstop pragma specifies a filename, the base name of the source file is used as the base name of the precompiled header file. This differs from the precompiled-header naming conventions of /YX; with /YX, the default name of the precompiled header is MSVC.PCH.

The filename specified in the hdrstop pragma is a string and is therefore subject to the constraints of any C or C++ string. In particular, you must escape backslashes ( \ ) when specifying paths. For example:

#pragma hdrstop( "d:\\include\\myinc.pch" )

You can also use preprocessing commands to perform macro replacement as follows:

#define INCLUDE_PATH "c:\\progra~`1\\devstsu~1\\vc\\include\\"
#define PCH_FNAME "PROG.PCH"
.
.
.
#pragma hdrstop( INCLUDE_PATH PCH_FNAME )

See Placement of the hdrstop Pragma for more guidelines.