Commit f633412

errno_t strerror_s(

char *buffer,

int errnum

);

errno_t _strerror_s(

char *buffer,

const char *strErrMsg

);

errno_t _wcserror_s(

wchar_t *buffer,

int errnum

);

errno_t __wcserror_s(

wchar_t *buffer,

const wchar_t *strErrMsg

);

template <size_t size>

*buffer*<br/>

Buffer to hold error string.

*errnum*<br/>

Error number.

|--------------|------------------------|-----------------|--------------------------|

|**NULL**|any|any|n/a|

|any|0|any|not modified|

If *strErrMsg* is **NULL**, **_strerror_s** returns a string in *buffer* containing the system error message for the last library call that produced an error. The error-message string is terminated by the newline character ('\n'). If *strErrMsg* is not equal to **NULL**, then **_strerror_s** returns a string in *buffer* containing (in order) your string message, a colon, a space, the system error message for the last library call producing an error, and a newline character. Your string message can be, at most, 94 characters long.

The actual error number for **_strerror_s** is stored in the variable [errno](../../c-runtime-library/errno-doserrno-sys-errlist-and-sys-nerr.md). The system error messages are accessed through the variable [_sys_errlist](../../c-runtime-library/errno-doserrno-sys-errlist-and-sys-nerr.md), which is an array of messages ordered by error number. **_strerror_s** accesses the appropriate error message by using the **errno** value as an index to the variable **_sys_errlist**. The value of the variable [_sys_nerr](../../c-runtime-library/errno-doserrno-sys-errlist-and-sys-nerr.md) is defined as the maximum number of elements in the **_sys_errlist** array. To produce accurate results, call **_strerror_s** immediately after a library routine returns with an error. Otherwise, subsequent calls to **strerror_s** or **_strerror_s** can overwrite the **errno** value.