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_ultoa, _ultow

Convert an unsigned long integer to a string.

char*_ultoa(unsignedlongvalue**,char*string,intradix);**

wchar_t*_ultow(unsignedlongvalue**,wchar_t*string,intradix);**

Routine Required Header Compatibility
_ultoa <stdlib.h> Win 95, Win NT
_ultow <stdlib.h> or <wchar.h> Win 95, Win NT

For additional compatibility information, see Compatibility in the Introduction.

Libraries

LIBC.LIB Single thread static library, retail version
LIBCMT.LIB Multithread static library, retail version
MSVCRT.LIB Import library for MSVCRT.DLL, retail version

Return Value

Each of these functions returns a pointer to string. There is no error return.

Parameters

value

Number to be converted

string

String result

radix

Base of value

Remarks

The _ultoa function converts value to a null-terminated character string and stores the result (up to 33 bytes) in string. No overflow checking is performed. radix specifies the base of value; radix must be in the range 2 – 36. _ultow is a wide-character version of _ultoa.

Generic-Text Routine Mappings

TCHAR.H Routine _UNICODE & _MBCS Not Defined _MBCS Defined _UNICODE Defined
_ultot _ultoa _ultoa _ultow

Example

/* ITOA.C: This program converts integers of various
 * sizes to strings in various radixes.
 */

#include <stdlib.h>
#include <stdio.h>

void main( void )
{
   char buffer[20];
   int  i = 3445;
   long l = -344115L;
   unsigned long ul = 1234567890UL;

   _itoa( i, buffer, 10 );
   printf( "String of integer %d (radix 10): %s\n", i, buffer );
   _itoa( i, buffer, 16 );
   printf( "String of integer %d (radix 16): 0x%s\n", i, buffer );
   _itoa( i, buffer, 2  );
   printf( "String of integer %d (radix 2): %s\n", i, buffer );

   _ltoa( l, buffer, 16 );
   printf( "String of long int %ld (radix 16): 0x%s\n", l,
                                                    buffer );

   _ultoa( ul, buffer, 16 );
   printf( "String of unsigned long %lu (radix 16): 0x%s\n", ul,
                                                    buffer );
}

Output

String of integer 3445 (radix 10): 3445
String of integer 3445 (radix 16): 0xd75
String of integer 3445 (radix 2): 110101110101
String of long int -344115 (radix 16): 0xfffabfcd
String of unsigned long 1234567890 (radix 16): 0x499602d2

Data Conversion Routines

See Also   _itoa, _ltoa