Header File 

stdio.h 

Category 

Memory and String Manipulation Routines 

Syntax 

int _snprintf(char* buffer, size_t nsize, const char* format, ...); 

int _snwprintf(wchar_t* buffer, size_t nsize, const wchar_t* format, ...); 

Description 

Sends formatted output to a string of a maximum length specified by nsize. _snprintf and _snwprintf are Microsoft compatible with the _snprintf and _snprintfw functions, respectively. 

If the number of bytes to output is:

• < nsize, then all of the characters have been written, including the terminating ‘\0’ character.
• == nsize, then nsize characters are written with no terminating ‘\0’ character.

If nsize is 0, then the string will not be written to (and may be NULL). 

If nsize is too small, then return value is -1, and only nsize characters are written, with no terminating ‘\0’ character. 

Return Value 

Number of bytes output or –1 if nsize is too small.