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 _MBCS or _UNICODE hasn't 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