_strrev, _wcsrev, _mbsrev, _mbsrev_l
Reverse characters of a string.
char *_strrev(
char *str
);
wchar_t *_wcsrev(
wchar_t *str
);
unsigned char *_mbsrev(
unsigned char *str
);
unsigned char *_mbsrev_l(
unsigned char *str,
_locale_t locale
);
Parameters
str
Null-terminated string to reverse.locale
Locale to use.
Return Value
Returns a pointer to the altered string. No return value is reserved to indicate an error.
Remarks
The _strrev function reverses the order of the characters in string. The terminating null character remains in place. _wcsrev and _mbsrev are wide-character and multibyte-character versions of _strrev. The arguments and return value of _wcsrev are wide-character strings; those of _mbsrev are multibyte-character strings. For _mbsrev, the order of bytes in each multibyte character in string is not changed. These three functions behave identically otherwise.
_mbsrev validates its parameters. If either string1 or string2 is a null pointer, the invalid parameter handler is invoked, as described in Parameter Validation. If execution is allowed to continue, _mbsrev returns NULL and sets errno to EINVAL. _strrev and _wcsrev do not validate their parameters.
The output value is affected by the setting of the LC_CTYPE category setting of the locale; see setlocale for more information. The versions of these functions without the _l suffix use the current locale for this locale-dependent behavior; the versions with the _l suffix are identical except that they use the locale parameter passed in instead. For more information, see Locale.
Security Note These functions incur a potential threat brought about by a buffer overrun problem. Buffer overrun problems are a frequent method of system attack, resulting in an unwarranted elevation of privilege. For more information, see Avoiding Buffer Overruns.
Generic-Text Routine Mappings
TCHAR.H routine |
_UNICODE & _MBCS not defined |
_MBCS defined |
_UNICODE defined |
|---|---|---|---|
_tcsrev |
_strrev |
_mbsrev |
_wcsrev |
n/a |
n/a |
_mbsrev_l |
n/a |
Requirements
Routine |
Required header |
|---|---|
_strrev |
<string.h> |
_wcsrev |
<string.h> or <wchar.h> |
_mbsrev, _mbsrev_l |
<mbstring.h> |
For additional compatibility information, see Compatibility in the Introduction.
Example
// crt_strrev.c
// This program checks a string to see
// whether it is a palindrome: that is, whether
// it reads the same forward and backward.
//
#include <string.h>
#include <stdio.h>
int main( void )
{
char* string = "Able was I ere I saw Elba";
int result;
// Reverse string and compare (ignore case):
result = _stricmp( string, _strrev( _strdup( string ) ) );
if( result == 0 )
printf( "The string \"%s\" is a palindrome\n", string );
else
printf( "The string \"%s\" is not a palindrome\n", string );
}
The string "Able was I ere I saw Elba" is a palindrome
.NET Framework Equivalent
Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.