StringCchLength function

Determines whether a string exceeds the specified length, in characters.

StringCchLength is a replacement for the following functions:

• strlen, wcslen, _tcslen

Syntax

HRESULT StringCchLength(
  _In_  LPCTSTR psz,
  _In_  size_t  cchMax,
  _Out_ size_t  *pcch
);

Parameters

psz [in]

Type: LPCTSTR

The string whose length is to be checked.

cchMax [in]

Type: size_t

The maximum number of characters allowed in psz, including the terminating null character. This value cannot exceed STRSAFE_MAX_CCH.

pcch [out]

Type: size_t*

The number of characters in psz, not including the terminating null character. This value is valid only if pcch is not NULL and the function succeeds.

Return value

Type: HRESULT

This function can return one of the following values. It is strongly recommended that you use the SUCCEEDED and FAILED macros to test the return value of this function.

Note that this function returns an HRESULT value, unlike the functions that it replaces.

Remarks

Compared to the functions it replaces, StringCchLength is an additional tool for proper buffer handling in your code. Poor buffer handling is implicated in many security issues that involve buffer overruns.

StringCchLength can be used in its generic form, or in its more specific forms. The data type of the string determines the form of this function that you should use.

Requirements

See also

StringCbLength