What does this mean?

[RedSon]

#define _AFX_FUNCNAME(_ Name) _Name##W

Whats the ##W part of that?

[gpraghuram]

#define _AFX_FUNCNAME(_ Name) _Name##W

Whats the ##W part of that?

##W concatenates the W with the value passed to the #define.

Change theW to _Name and print the value like this
[code=c]
#define _AFX_FUNCNAME(_ Name) _Name##_Name

printf("%s\n",_ AFX_FUNCNAME("t est"));

[/code]

Raghuram

[RedSon]

##W concatenates the W with the value passed to the #define.

Change theW to _Name and print the value like this
[code=c]
#define _AFX_FUNCNAME(_ Name) _Name##_Name

printf("%s\n",_ AFX_FUNCNAME("t est"));

[/code]

Raghuram

So the output would be "_Nametest_Name "?

[gpraghuram]

So the output would be "_Nametest_Name "?

No i got a different output like "testtest"


Raghuram

[weaknessforcats]

Read up on the preprocessor token-pasting operator.

This is replaced in C++ with templates.