A Sample Generic-Text Program

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The latest version of this topic can be found at A Sample Generic-Text Program.

Microsoft Specific**

The following program, GENTEXT.C, provides a more detailed illustration of the use of generic-text mappings defined in TCHAR.H:

// GENTEXT.C  
// use of generic-text mappings defined in TCHAR.H  
  
#include <stdio.h>  
#include <stdlib.h>  
#include <string.h>  
#include <direct.h>  
#include <errno.h>  
#include <tchar.h>  
  
int __cdecl _tmain(int argc, _TCHAR **argv, _TCHAR **envp)  
{  
   _TCHAR buff[_MAX_PATH];  
   _TCHAR *str = _T("Astring");  
   char *amsg = "Reversed";  
   wchar_t *wmsg = L"Is";  
  
#ifdef _UNICODE  
   printf("Unicode version\n");  
#else /* _UNICODE */  
#ifdef _MBCS  
   printf("MBCS version\n");  
#else  
   printf("SBCS version\n");  
#endif  
#endif /* _UNICODE */  
  
   if (_tgetcwd(buff, _MAX_PATH) == NULL)  
       printf("Can't Get Current Directory - errno=%d\n", errno);  
   else  
       _tprintf(_T("Current Directory is '%s'\n"), buff);  
   _tprintf(_T("'%s' %hs %ls:\n"), str, amsg, wmsg);  
   _tprintf(_T("'%s'\n"), _tcsrev(_tcsdup(str)));  
   return 0;  
}  
  

If _MBCS has been defined, GENTEXT.C maps to the following MBCS program:

// crt_mbcsgtxt.c  
  
/*   
 * Use of generic-text mappings defined in TCHAR.H  
 * Generic-Text-Mapping example program  
 * MBCS version of GENTEXT.C  
 */  
  
#include <stdio.h>  
#include <stdlib.h>  
#include <mbstring.h>  
#include <direct.h>  
  
int __cdecl main(int argc, char **argv, char **envp)  
{  
   char buff[_MAX_PATH];  
   char *str = "Astring";  
   char *amsg = "Reversed";  
   wchar_t *wmsg = L"Is";  
  
   printf("MBCS version\n");  
  
   if (_getcwd(buff, _MAX_PATH) == NULL) {  
       printf("Can't Get Current Directory - errno=%d\n", errno);  
   }  
   else {  
       printf("Current Directory is '%s'\n", buff);  
   }  
  
   printf("'%s' %hs %ls:\n", str, amsg, wmsg);  
   printf("'%s'\n", _mbsrev(_mbsdup((unsigned char*) str)));  
   return 0;  
}  

If _UNICODE has been defined, GENTEXT.C maps to the following Unicode version of the program. For more information about using wmain in Unicode programs as a replacement for main, see Using wmain in C Language Reference.

// crt_unicgtxt.c  
  
/*   
 * Use of generic-text mappings defined in TCHAR.H  
 * Generic-Text-Mapping example program  
 * Unicode version of GENTEXT.C  
 */  
  
#include <stdio.h>  
#include <stdlib.h>  
#include <string.h>  
#include <direct.h>  
  
int __cdecl wmain(int argc, wchar_t **argv, wchar_t **envp)  
{  
   wchar_t buff[_MAX_PATH];  
   wchar_t *str = L"Astring";  
   char *amsg = "Reversed";  
   wchar_t *wmsg = L"Is";  
  
   printf("Unicode version\n");  
  
   if (_wgetcwd(buff, _MAX_PATH) == NULL) {  
      printf("Can't Get Current Directory - errno=%d\n", errno);  
   }  
   else {  
       wprintf(L"Current Directory is '%s'\n", buff);  
   }  
  
   wprintf(L"'%s' %hs %ls:\n", str, amsg, wmsg);  
   wprintf(L"'%s'\n", wcsrev(wcsdup(str)));  
   return 0;  
}  

If neither _MBCS nor _UNICODE has been defined, GENTEXT.C maps to single-byte ASCII code, as follows:

// crt_sbcsgtxt.c  
/*   
 * Use of generic-text mappings defined in TCHAR.H  
 * Generic-Text-Mapping example program  
 * Single-byte (SBCS) Ascii version of GENTEXT.C  
 */  
  
#include <stdio.h>  
#include <stdlib.h>  
#include <string.h>  
#include <direct.h>  
  
int __cdecl main(int argc, char **argv, char **envp)  
{  
   char buff[_MAX_PATH];  
   char *str = "Astring";  
   char *amsg = "Reversed";  
   wchar_t *wmsg = L"Is";  
  
   printf("SBCS version\n");  
  
   if (_getcwd(buff, _MAX_PATH) == NULL) {  
       printf("Can't Get Current Directory - errno=%d\n", errno);  
   }  
   else {  
       printf("Current Directory is '%s'\n", buff);  
   }  
  
   printf("'%s' %hs %ls:\n", str, amsg, wmsg);  
   printf("'%s'\n", strrev(strdup(str)));  
   return 0;  
}  

END Microsoft Specific

See Also

Generic-Text Mappings
Data Type Mappings
Constant and Global Variable Mappings
Routine Mappings
Using Generic-Text Mappings