#include absolute path syntax in c/c++

Question

For some reason, I need to use the absolute path in #include for my system.

Is using #include \"D:\\temp\\temp_lib\\temp.h\" acceptable?

Answer 1

Every implementation I'm aware of, and certainly MSVC 2005 and linux, allows you to specify the directory paths in which to find header files. You should include D:\temp\temp_lib on the list of directory paths, and then use

#include <temp.h>

For gcc, use -I path. For MSVC, see Where does Visual Studio look for C++ header files?

The reason that #1 isn't a syntax error is that, although it looks like a string literal, it isn't. The specification is

#include "q-char-sequence"

Where q-char is

any member of the source character set except the new-line character and "

In particular, \ has no special meaning. The interpretation of the q-char-sequence is implementation-defined.