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Convert an unsigned long integer to a string. More secure versions of these functions are available; see _ultoa_s, _ultow_s.
char *_ultoa(
unsigned long value,
char *str,
int radix
);
wchar_t *_ultow(
unsigned long value,
wchar_t *str,
int radix
);
template <size_t size>
char *_ultoa(
unsigned long value,
char (&str)[size],
int radix
); // C++ only
template <size_t size>
wchar_t *_ultow(
unsigned long value,
wchar_t (&str)[size],
int radix
); // C++ only
Parameters
value
Number to be converted.str
String result.radix
Base of value*.*
Return Value
Each of these functions returns a pointer to str. There is no error return.
Remarks
The _ultoa function converts value to a null-terminated character string and stores the result (up to 33 bytes) in str. 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.
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To prevent buffer overruns, ensure that the str buffer is large enough to hold the converted digits plus the trailing null-character. |
In C++, these functions have template overloads that invoke the newer, secure counterparts of these functions. For more information, see Secure Template Overloads.
Generic-Text Routine Mappings
TCHAR.H routine |
_UNICODE & _MBCS not defined |
_MBCS defined |
_UNICODE defined |
---|---|---|---|
_ultot |
_ultoa |
_ultoa |
_ultow |
Requirements
Routine |
Required header |
---|---|
_ultoa |
<stdlib.h> |
_ultow |
<stdlib.h> or <wchar.h> |
For additional compatibility information, see Compatibility in the Introduction.
Example
See the example for _itoa.